China National Offshore Oil Co. (CNOOC) issued a tender offering for domestic and foreign companies to bid for 10 coalbed methane blocks in the country, the company said on April 21.

The blocks have a total size of 2,173 sq km, including blocks in the Ningxia region in western China, Shanxi province in central China, and Shandong, Anhui province in the east, the company said in a statement.

The data room for the tender is open from April 30 to July 31, the company said.