Three Chinese oil companies denied recent media reports that they had bid for oil exploration contracts in the South China Sea from the Philippine government, People's Daily reported.

Citing Jose Layug, Philippine energy undersecretary, AFP said on Aug 2 that China's State-owned China National Offshore Oil Corporation (CNOOC) is among the three.

Chinese media said that the other two are BGP Ltd, a subsidiary of China National Petroleum Corporation, and Polyard Petroleum International Group Ltd (PPIG).

The three companies denied taking part in such a bidding, People's Daily said.

A liaison officer from CNOOC told People's Daily that the head office knew nothing about the reported situation and declined to comment.

A senior manager of BGP, who declined to be identified, said the company is not among the bidders. "Never heard of it. We learned of the bidding from media reports," he said.

Lai Chun Liang, chief executive officer of PPIG, said the company knew of the bidding process but did not participate.

Layug told AFP that the 15 areas set for exploration cover more than 100,000 square kilometers, are far from the disputed Nansha Islands, and well within the Philippines' 200-nautical-mile (370 km)exclusive economic zone.

"These are not disputed areas. The area we are offering up for bids is definitely within the territory of the Republic of the Philippines," Layug was quoted as saying.

However, an unidentified Chinese official said that?a few of the 15 areas the Philippines set for bidding are entirely under Chinese jurisdiction and another four include both Chinese and Philippine territory.

The Chinese embassy to the Philippines lodged a formal complaint in June, when the Philippine government announced the bidding.

Liu Jianchao, Chinese ambassador to the Philippines, said China indisputably owns the Nansha Islands and called for countries to stop oil exploration without China's consent, People's Daily said.

Chinese authorities are requesting more information from the Philippine government.