Millicom International Cellular S A : Convening Notice for AGM and EGM of Shareholders 2024

Convening Notice for Annual General Meeting and Extraordinary

General Meeting of Shareholders

MILLICOM INTERNATIONAL CELLULAR S.A.

Registered Address: 2, Rue du Fort Bourbon

L-1249 Luxembourg, Grand Duchy of Luxembourg

- R.C.S. Luxembourg: B 40.630 -

1. NOTICE

The annual general meeting ("AGM") and subsequent extraordinary general meeting ("EGM") of the shareholders of MILLICOM INTERNATIONAL CELLULAR S.A. ("Millicom" or the "Company") is hereby convened to be held at Hotel Le Royal, 12 Bd Royal, 2449 Luxembourg on Thursday, May 23, 2024, at 11:00 a.m. Central European Time("CET").

To attend the AGM and EGM or vote by proxy, please follow the instructions in section IV: "Right to participate at the AGM and the EGM".

The AGM and EGM will consider and vote on the agenda points listed below. Please refer to section IX: "Notes to the Agenda Points of the AGM and EGM"to find detailed information about these proposals.

1. AGENDA

AGM

1. To elect the chair of the AGM and to empower the chair of the AGM to appoint the other members of the bureau of the meeting.[Note]
2. To receive the management reports of the board of directors (the "Board") and the reports of the external auditor on the annual accounts and the consolidated accounts for the year ended December 31, 2023.
3. To approve the annual accounts and the consolidated accounts for the year ended December 31, 2023.
4. To allocate USD 7,560,803 of the results of the year ended December 31, 2023 to the legal reserve and the remaining balance to the unappropriated net profits to be carried forward. [Note]
5. To discharge all the Directors of Millicom for the performance of their mandates during the year ended December 31, 2023.[Note]
6. To set the number of Directors at 9.[Note]

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1. To re-elect María Teresa Arnal as a Director for a term ending at the annual general meeting to be held in 2025 (the "2025 AGM"). [Note]
2. To re-elect Bruce Churchill as a Director for a term ending at the 2025 AGM. [Note]
3. To re-elect Tomas Eliasson as a Director for a term ending at the 2025 AGM. [Note]
4. To re-elect Mauricio Ramos as a Director for a term ending at the 2025 AGM. [Note]
5. To re-elect Thomas Reynaud as a Director for a term ending at the 2025 AGM. [Note]
6. To re-elect Blanca Treviño de Vega as a Director for a term ending at the 2025 AGM. [Note]
7. To re-elect Aude Durand as a Director for a term ending at the 2025 AGM. [Note]
8. To elect Maxime Lombardini as a Director for a term ending at the 2025 AGM.[Note]
9. To elect Justine Dimovic as a Director for a term ending at the 2025 AGM.[Note]
10. To elect Mauricio Ramos as Chair of the Board for a term ending at the 2025 AGM.[Note]
11. To approve the Directors' remuneration for the period from the AGM to the 2025 AGM.[Note]
12. To elect KPMG Audit SARL and KPMG LLP (collectively, "KPMG") as the external auditor for a term ending on the date of the 2025 AGM and to approve the external auditor remuneration to be paid against an approved account. [Note]
13. To approve an instruction to the Nomination Committee.[Note]
14. To approve the Share Repurchase Plan. [Note]
15. To vote on the 2023 Remuneration Report. [Note]
16. To approve the Senior Management Remuneration Policy. [Note]
17. To approve the share-based incentive plans for Millicom employees. [Note]

EGM

1. To elect the chair of the EGM and to empower the chair of the EGM to appoint the other members of the bureau of the meeting. [Note]
2. To remove the casting vote of the Chair of the Board in the event of a tie provided by article 444-4 (2) of the 1915 Law and add a sentence to paragraph 7 of article 8 of Millicom's articles of association expressly stating that the Chair of the Board does not have a casting vote in the event of a tie. [Note]
3. To adopt inclusive language and change the definition from "Chairman" to "Chair" of the Board, and to amend article 7, 8, 9 and 21 of Millicom's articles of association accordingly, and further amend article 19 second sentence of Millicom's articles of association to refer to the "chair of the annual general meeting". [Note]
4. To fully restate the Company's articles of association to incorporate the amendments to the Company's articles of association approved in the foregoing resolutions. [Note]

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The following persons who comply with the procedure below, and hold shares or Swedish Depository Receipts ("SDRs") on May 9, 2024, at 24.00 CET (the "Voting Record Date") are eligible to participate/vote at the AGM and EGM1:

1. Holders of Millicom shares traded on the Nasdaq Stock Market in the US ("Nasdaq US") under the ticker symbol TIGO ("Millicom Shareholders") that are registered with Broadridge Corporate Issuer Solutions, Inc. ("Broadridge"), including those held by Cede & Co ("DTCC"), and
2. Holders of SDRs traded on Nasdaq Stockholm under the ticker symbol TIGO SDB ("Millicom SDR Holders") that are registered with Euroclear Sweden AB ("Euroclear Sweden"). Since the Record Date is a public holiday in Sweden, holders of SDRs must make certain that they are registered in the records maintained by Euroclear Sweden AB on May 8, 2024, at 23.59 CET.

Conversion stoppage. Conversions from SDRs into shares, and vice versa, will not be permitted from and including May 6, 2024, up to and including May 9, 2024. Millicom SDR Holders and Millicom Shareholders who seek to convert their SDRs to shares, or vice versa (which can be done in accordance with the procedures set out on Millicom's website at Millicom-SDR-conversion-process), should take into consideration the dates and times noted above.

Instructions for participating and voting by Millicom Shareholders are shown below. Instructions for participation and voting by Millicom SDR Holders are shown on the following page.

1. Millicom Shareholders (US)

Millicom Shareholders eligible to participate and vote

Participation and voting at the AGM and the EGM is reserved to Millicom Shareholders duly registered with Broadridge and/or held by DTCC, on the Voting Record Date (as defined above) at 24.00 CET and who comply with these procedures.

1 However, notwithstanding anything to the contrary herein, the Bureau of the AGM/EGM shall have the discretionary power to exceptionally accept the voting of a shareholder or SDR holder at the AGM/EGM, even if the relevant proxy or notification form have a formal deficiency or was received after the deadlines contained herein.

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Beneficial owners. Beneficial owners of shares that are registered in the name of a nominee or broker (including nominees or brokers that hold shares through DTCC) have the right to instruct their nominee or broker on how to vote with a voter instruction form ("VIF"), or as may otherwise be established by the nominee or broker.

Beneficial owners who wish to attend the AGM and the EGM or vote directly must request the nominee or broker, that appears as the registered shareholder on the Voting Record Date, to issue a legal proxy which allows the beneficial owner to vote his or her shares directly.

Beneficial owners who do not vote via their brokers/nominees or do not have a legal proxy are not eligible to vote.

Ways to participate and deadline

1. By proxy: registered shareholders may submit the power of attorney form ("Millicom Shareholder Proxy Form") containing their voting instructions, such that it is received no later than on May 17, 2024.
2. In person: the registered shareholder may submit the notification of attendance form to attend the AGM and/or the EGM in person (the "Millicom Shareholder Notification Form"), such that it is received no later than on the Voting Record Date (May 9).

Channels to submit the Millicom Shareholder Proxy Form and the Millicom Shareholder Notification Form

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1. Online: The Company has sent by post the invitation letter and the Millicom Shareholder Proxy Form needed to vote at the AGM and EGM. The Millicom Shareholder Proxy Form includes a control number. Votes can be cast online using the control number at https://east.proxyvote.com/pv/web
   If you consider that you are eligible to vote but you have not received the control number by post and you would like to submit your vote online, please contact Millicom at information@millicom.com
2. By post: The Millicom Shareholder Proxy Form and the Millicom Shareholder Notification Form can be submitted by post. The original completed, dated and signed Millicom Shareholder Proxy Form or Millicom Shareholder Notification Form should be mailed to the address provided in the form. Millicom Shareholders that choose to send the Millicom Shareholder Proxy Form or the Millicom Shareholder Notification Form by post should also send a scanned copy to information@millicom.com
3. By e-mail (only for the Millicom Shareholder Notification Form): Download the Millicom Shareholder
   Notification Form from the Millicom Website: https://www.millicom.com/our-company/governance/shareholder-meetings/.Complete, date and sign the form using an electronic signature, and send the signed form to information@millicom.com

Millicom Shareholder Proxy Forms, Millicom Shareholder Notification Form and all supporting documents can be downloaded from Millicom's website: https://www.millicom.com/our-company/governance/shareholder-meetings/

Evidence of authority (for Millicom Shareholder Notification Forms only)

If a shareholder is a legal entity, the Millicom Shareholder Notification Form must be signed by a duly authorized person and sufficient evidence of the signatory's legal power of representation must be provided. Any physical attendee at the AGM and EGM will need to bring original identification documentation (e.g., passport).

2. Millicom SDR Holders (Sweden)

Millicom SDR Holders eligible to participate and vote

Participation and voting at the AGM and/or the EGM is reserved to Millicom SDR Holders duly registered with Euroclear Sweden as of the Voting Record Date (as defined above) at 24.00 CET and who comply with these procedures. Since the Record Date is a public holiday in Sweden, holders of SDRs must make certain that they are registered in the records maintained by Euroclear Sweden AB on May 8, 2024, at 23.59 CET.

Re-registration. In order to exercise their rights at the AGM and/or EGM, Millicom SDR Holders whose SDRs are registered in the name of a broker or nominee must temporarily re-register the SDRs in their own name in the records maintained by Euroclear Sweden. Millicom SDR Holders wishing to re-register must inform their broker/nominee well in advance of the Voting Record Date so that they appear on the records maintained by Euroclear Sweden at 24.00 CET on the Voting Record Date.

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Note that the re-registration process can take 10 business days or more, and Millicom SDR Holders who have not re-registered will not be eligible to participate and vote at the AGM / EGM. As such, we strongly recommend commencing the re-registrationprocess as soon as possible.

Ways to participate and deadline

1. By proxy: registered Millicom SDR Holders may submit the power of attorney form ("Millicom SDR Holder Proxy Form") containing their voting instructions, such that it is received no later than on May 17, 2024.
2. In person: the registered Millicom SDR Holder may submit the SDR Holder notification of attendance form to attend the AGM and the EGM in person (the "Millicom SDR Holder Notification Form"), such that it is received no later than on the Voting Record Date (May 9, 2024)

Channels to submit the Millicom SDR Holder Proxy Form and the Millicom SDR Holder Notification Form

1. Online: The Company has sent by post the invitation letter to vote at the AGM and EGM. The invitation letter includes a pin code. Votes can be cast using the pin code online at https://anmalan.vpc.se/euroclearproxy.

Alternatively, Millicom SDR Holders with a Swedish BankID (available for Swedish individuals only) can vote online at https://anmalan.vpc.se/euroclearproxyusing the BankID (instead of the pin- code).

If you are a Millicom SDR Holder eligible to vote at the AGM/EGM but have not received the invitation letter, and you would like to submit your vote online, please contact Euroclear Sweden at: millicom@euroclear.comor by phone: +468-401-43-11 between 9:00 a.m. and 4:00 p.m. CET.

1. By post: The Millicom SDR Holder Proxy Form and Millicom SDR Holder Notification Form can be submitted by post. The original completed, dated and signed forms shall be mailed to the address provided in the form.
   Millicom SDR Holders that choose to send the SDR Holder Proxy Form or Millicom SDR Holder Notification Form by post should also send a scanned copy to: millicom@euroclear.com
2. By e-mail (only for the Millicom SDR Holder Notification Form): Download the Millicom SDR Holder
   Notification Form from the Millicom Website: https://www.millicom.com/our-company/governance/shareholder-meetings/.Complete, date and sign the form using an electronic signature, and email the signed form to millicom@euroclear.com

Millicom SDR Holder Proxy Forms, Millicom SDR Holder Notification Form and all supporting documents can be downloaded from Millicom's website: https://www.millicom.com/our-company/governance/shareholder-meetings/

Evidence of authority (for Millicom SDR Holder Notification Form only)

If the Millicom SDR Holder is a legal entity, the Millicom SDR Holder Notification Form must be signed by a duly authorized person and legally sufficient evidence of the signatory's power of representation

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must be provided. The attendee will also need to bring an original identification document (such as a passport).

1. SHARE CAPITAL, QUORUM, AND MAJORITY

As of April 16, 2024, Millicom had 172,096,305 outstanding shares, each with nominal value of USD 1.50, and each share is entitled to one vote. As of April 16, 2024, Millicom held 766,703 shares in treasury. The number of shares held in treasury by Millicom will be updated on the Voting Record Date to calculate the voting results. Voting rights attached to shares held in treasury are suspended by law.

There is no quorum of presence requirement for the AGM. The AGM agenda items are adopted by a simple majority of the shares present or represented (excluding abstentions).

The EGM will validly deliberate on the resolutions on its agenda only if at least 50% of the issued share capital is present or represented (the "Quorum") at the first meeting and will validly be adopted only if approved by at least 2/3rds of the votes cast at the EGM. If the Quorum is not reached at the first meeting, the Board of Directors may convene a second extraordinary general meeting with an identical agenda as for the EGM, at which no quorum will be required, and at which the resolutions will validly be adopted if approved by at least 2/3rds of the votes cast at the second EGM.

VI. RIGHT TO PROPOSE NEW ITEMS TO THE AGENDA

One or several shareholders representing, individually or collectively, at least 5% of the share capital of Millicom reserve the right to add additional items to the agenda of the AGM and/or EGM.

These rights shall be exercised in writing and submitted to Millicom by mail at Millicom's Registered Address, attention: Company Secretary, and by e-mail to information@millicom.com, such that they are received no later than May 2, 2024, and the revised agenda will be published by Millicom, no later than May 8, 2024. Shareholder(s) requesting to add an item to the agenda must provide:

1. a reason or motivation for such petition,
2. a draft of the resolution to be presented at the AGM or EGM, and
3. a postal and e-mail address to which the acknowledgment of receipt of their request may be sent by Millicom. Such acknowledgment will be sent within forty-eight (48) hours of receipt of the request.

VII. ABILITY TO ASK QUESTIONS AHEAD OF THE AGM AND THE EGM

Shareholders have the right to ask questions about items on the agenda of the AGM and the EGM ahead of the meeting. The Company will on a reasonable-efforts basis provide responses to the questions on the Company's website. Questions must be received by the Company by May 17, 2024. Questions must be sent by e-mail to: information@millicom.comand include the shareholder's full name and address and proof of ownership of Millicom shares on the Voting Record Date.

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VIII. SUPPORTING DOCUMENTS AND INFORMATION

The following documents and information related to the AGM and EGM are available to shareholders at the Registered Address of Millicom and on Millicom's website www.millicom.com/our-company/governance/shareholder-meetings/:

• this Convening Notice;
• the Millicom Shareholder Proxy Form and the Millicom Shareholder Notification Form - Nasdaq US;
• the Millicom SDR Holder Proxy Form and the Millicom SDR Holder Notification Form - Nasdaq Stockholm;
• the draft resolutions of the AGM;
• • Millicom's annual accounts and consolidated accounts for the year ended December 31, 2023, together with the management report(s) of the Board and the report(s) of the external auditor on the annual accounts and consolidated accounts;
• U.S. General Federal Income Tax Considerations for U.S. holders of Millicom shares and SDRs;
• the Nomination Committee's motivated statement explaining its proposals regarding the Board and information on the proposed Directors;
• the 2023 Remuneration Report;
• the draft resolutions of the EGM; and
• the draft restated articles of association of the Company.

Shareholders may also receive a copy of the above-mentioned documents by sending a request by mail to the Millicom Registered Address, attention: Company Secretary, or by e-mail to information@millicom.com.

IX. NOTES TO THE AGENDA POINTS OF THE AGM AND THE EGM

AGM - item 1: CHAIR OF THE MEETING

Millicom's Nomination Committee proposes Mr. Alexander Koch, attorney at law (Avocat à la Cour/Rechtsanwalt), with professional address in Luxembourg, to preside over the AGM.

In the event of Mr. Alexander Koch's absence, the Chair of the Board - or in the absence of the Chair of the Board, any member of the Board present at the AGM - shall be empowered to appoint from amongst the persons present at the AGM the individual that will preside over the AGM.

The chair of the AGM shall be empowered to appoint, from among the persons present or virtually present at the meeting the other members of the bureau of the meeting (i.e., the Secretary and the Scrutineer).

AGM - item 4: RESULTS ALLOCATION

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On a parent-company basis, Millicom generated a profit of USD 344,874,950 for the fiscal year ended December 31, 2023 (the "2023 Results"). In compliance with 1915 Law, the Board proposes (i) to allocate USD 7,560,803 of the 2023 Results to the legal reserve to reach 10% of the share capital (i.e., therefore, the total legal reserve amounts to USD 25,814,446), and (ii) the remaining USD 337,314,147 to unappropriated net profits to be carried forward.

AGM - item 5: DISCHARGE OF DIRECTORS FOR THEIR PERFORMANCE

To discharge of all the current and former Directors of Millicom who served at any point in time during the financial year ended December 31, 2023, for the performance of their mandates.

AGM - items 6-16: ELECTION OF THE DIRECTORS

The Nomination Committee proposes that the Board shall consist of nine (9) directors.

The Nomination Committee proposes that María Teresa Arnal, Bruce Churchill, Aude Durand, Tomas Eliasson, Mauricio Ramos, Thomas Reynaud and Blanca Treviño de Vega be re-elected as Directors of Millicom for the term beginning at the AGM and ending at the 2025 AGM.

The Nomination Committee proposes that Maxime Lombardini and Justine Dimovic be elected as new Directors of Millicom for the term beginning at the AGM and ending at the 2025 AGM.

Pernille Erenbjerg and Michael Golan have decided not to seek re-election as Directors of Millicom.

The Nomination Committee, supported by the Board, proposes that Mauricio Ramos be elected as Chair of the Board for a term beginning at the AGM and ending at the 2025 AGM.

The Nomination Committee's motivated statement regarding the Board's composition is available on Millicom's website.

AGM - item 17: DIRECTORS' REMUNERATION POLICY AND FEES

Directors' Remuneration Policy

In proposing remuneration for the Directors, the Nomination Committee considers many factors, including the size and complexity of the business, the number of board and committee meetings, the amount of responsibility related to each role, regulatory requirements, as well as market practice. The Nomination Committee may also appoint an external compensation consultant to provide advice and benchmarking. The Chair of the Board of Millicom does not participate in discussions or decision-making regarding Director remuneration.

Remuneration to Directors comprises cash-based and share-based components, weighted toward shares to align with the compensation philosophy and guidelines of the Company set out in item 22. Directors appointed to Board Committees receive cash-based compensation for each appointment.

Share-based compensation is in the form of fully paid-up shares of Millicom common stock. There are no retention, vesting or other holding conditions attached to the shares. Such shares are provided from the Company's treasury shares or alternatively issued within Millicom's authorized share capital exclusively in

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exchange for allocation from the premium reserve (i.e., for nil consideration from the relevant Directors). Share-based compensation is calculated by dividing the approved remuneration by the average Millicom closing share price on the Nasdaq Stock Market in the US for the three-month period ending on April 30, 2024, provided that shares shall not be issued below par value.

Notwithstanding the above, for any period where a Director is also an employee of Millicom, no remuneration is paid to that Director beyond any compensation received as an employee of Millicom.

Directors' Remuneration

The Nomination Committee proposes the compensation for the period from the date of the AGM to the date of the 2025 AGM, as follows:

• Not payable while the Chair or a Board member receives compensation as an employee of Millicom. Final number of committee members to be set by the Board and subject to modification.

AGM - item 18: ELECTION OF THE AUDITOR AND FEES

The Nomination Committee, in accordance with the recommendation of Millicom's Audit and Compliance Committee, proposes that KPMG be elected as external auditor for a term beginning at the AGM and ending at the 2025 AGM.

The proposal from the Nomination Committee, and recommendation from the Audit and Compliance Committee, is based on a tender and evaluation of external audit firms conducted in Q1 2024, taking into consideration independence requirements and fees, among other factors.

The Nomination Committee proposes that the auditor's remuneration be paid against an approved account.

AGM - item 19: INSTRUCTION TO THE NOMINATION COMMITTEE

The Nomination Committee proposes that the following Instruction to the Nomination Committee shall apply until new instructions have been adopted. In the event any applicable law or stock market regulation requires a change to this procedure, the Nomination Committee shall take any steps necessary or proper to ensure compliance with such rules.

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