LONDON (Reuters) - WPP (>> WPP Group), the world's biggest advertising agency, said it was still working with its IT partners to restore services hit by the Petya ransomware attack that went around the world on Tuesday.

WPP had joined other companies such as shipping giant A.P. Moller-Maersk (>> AP Moller-Maersk) in reporting disruption to its operations due to a cyber attack.

"We are working with our IT partners and law enforcement agencies to take all appropriate precautionary measures, restore services where they have been disrupted, and keep the impact on clients, partners and our people to a minimum," the company said in a statement on Wednesday.

"Our operations have not been uniformly affected, and issues are being addressed on a company-by-company basis. Many of our businesses are experiencing no or minimal disruption."

(Reporting by Kate Holton; Editing by Susan Fenton)

Stocks treated in this article : AP Moller-Maersk, WPP Group