London’s listed oil explorers will be among those bidding to work with China National Offshore Oil Corporation (Cnooc) after it offered 25 offshore blocks to foreign firms.

Cnooc, the largest state-run offshore oil producer in the People’s Republic, announced that it is looking for cooperation projects with overseas companies for an unprecedented 25 blocks, covering a total area of 102,577 sq km.

The move comes as China strives to increase domestic oil output in the face of a growing crude deficit.

Crude oil demand from the People’s Republic is growing faster than supply, with Chinese government data showing supply has grown an average of 2.2% annually since 2002 but oil demand is expected to grow by about 4% this year and next.

A statement from Cnooc said 17 of the blocks were located in the South China Sea, including 15 blocks of deep-water depth, three blocks in the East China Sea and five in the Yellow Sea and Bohai Sea, with none of the blocks positioned in disputed territorial waters.

Last year Cnooc offered 26 blocks, of which six required deep-water drilling.

The state-run company explained that foreign companies may access the data related to the blocks once they had applied for the projects, with data to be made available until December 30th.

Cnooc has previously outlined plans to double its oil and gas production by 2020 and triple it by 2030 from 2010 levels.

London-listed companies with existing interests in Asia include Royal Dutch Shell, BP and Premier Oil.