CNOOC Limited Announces Its Satisfactory Results in All Business Aspects in 1H2013

(Hong Kong, August 20, 2013) - CNOOC Limited (the "Company", NYSE: CEO, SEHK: 00883) today announced its interim results ended June 30, 2013.

For the first half of the year, the Company's total net oil and gas production rose 23.1% year-on-year (YOY) to 198.1 million barrels of oil equivalent (BOE), in which Nexen contributed 24.8 million BOE. Without Nexen's production output, the production growth was 7.7%.

Mainly attributed to the reduced price of the fuel oil and petroleum product in the Far East, the Company's average realized oil price dropped to US$104.20 per barrel, representing a decrease of 10.9% YOY. Affected by the lower realized natural gas price of Nexen, the Company's average realized natural gas price declined 3.7% YOY to US$5.68 per thousand cubic feet.

Benefited from the rising net oil and gas production, the oil and gas sales and net profit of the Company reached RMB110.8 billion and RMB34.4 billion, representing an increase of 15.8% and 7.9% YOY respectively. The Company's all-in cost increased 22.4% YOY to US$42.36 per BOE, primarily due to the acquisition of Nexen. Taking out Nexen's impact, the all-in cost would be US$37.81 per BOE, representing an increase of 9.3% YOY.

In the area of exploration, the Company made 7 new discoveries and 18 successful appraisal wells in offshore China. The discovery of Bozhong 8-4 indicated an important breakthrough of Neogene from uplift to sag and created a new exploration area in the west slope of Bozhong sag. In the meanwhile, the new discovery of Kenli 10-4 uncovers the new area of oil and gas exploration in the north slope of Laizhou bay sag.

In the area of overseas, the Company has completed the acquisition of Nexen on 26 February. The integration work after the transaction has made impressive progress. Meanwhile, we are working diligently towards getting the Company listed at Toronto Stock Exchange (TSX).

Mr. Wang Yilin, Chairman of the Company commented, "During the first half of 2013, the Company achieved good performance in all aspects. While identifying what we have achieved, we will continue to strengthen risk management and control, technological and management innovation as well as building a talented team in order to raise our core competitiveness and capability for sustainable development, all working toward an even brighter future for the Company."

Mr. Li Fanrong, CEO of the Company commented, "During the first half of the year, the Company has made smooth progress in the areas of exploration, development and production as well as overseas development, maintaining a sound financial position and satisfactory results in all areas of our business. For the second half of the year, we will continue to enhance our businesses in a meticulous and conscientious manner."

In the first half of the year, the Company's basic earnings per share reached RMB0.77. In order to share our outstanding results with shareholders, the board has declared an interim dividend of HK$0.25 per share (tax inclusive).

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Notes to Editors:

More information about the Company is available at http://www.cnoocltd.com.

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This press release includes "forward-looking statements" within the meaning of the United States Private Securities Litigation Reform Act of 1995, including statements regarding expected future events, business prospectus or financial results. The words "expect", "anticipate", "continue", "estimate", "objective", "ongoing", "may", "will", "project", "should", "believe", "plans", "intends" and similar expressions are intended to identify such forward-looking statements. These statements are based on assumptions and analysis made by the Company in light of its experience and perception of historical trends, current conditions and expected future developments, as well as other factors that the Company believes reasonable under the circumstances. However, whether actual results and developments will meet the Company's expectations and predictions depends on a number of risks and uncertainties which could cause the actual results, performance and financial conditions to differ materially from the Company's expectations, including those associated with fluctuations in crude oil and natural gas prices, the exploration or development activities, the capital expenditure requirements, the business strategy, whether the transactions entered into by the Company can complete on schedule pursuant to its timetable or at all, the highly competitive nature of the oil and natural gas industries, the foreign operations, environmental liabilities and compliance requirements, and economic and political conditions in the People's Republic of China. For a description of these and other risks and uncertainties, please see the documents the Company has filed from time to time with the United States Securities and Exchange Commission, including 2012 Annual Report on Form 20-F filed on April 24, 2013.

Consequently, all of the forward-looking statements made in this press release are qualified by these cautionary statements. The Company cannot assure that the results or developments anticipated will be realized or, even if substantially realized, that they will have the expected effect on the Company, its business or operations.

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For further enquiries, please contact:
Ms. Michelle Zhang
Deputy Manager, Media/Public Relations
CNOOC Limited
Tel: +86-10-8452-6642
Fax: +86-10-8452-1441
E-mail: MR@cnooc.com.cn

Ms. Angela Hui
Ketchum Newscan Public Relations Ltd
Tel: +852-3141-8091
Fax: +852-2510-8199
E-mail: angela.hui@knprhk.com

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