Thanks to intensified exploration efforts, China's three major oil companies found more oil and natural gas reserves in 2004.

According to People's Daily, China National Petroleum Corp (CNPC) found 520 million tons of new oil reserves and 243.6 billion cubic meters of natural gas reserves in six regions in 2004.

Sinopec found 328 million tons of new oil reserves and 177.9 billion cubic meters of natural gas reserves last year.

China National Offshore Oil Corporation also found two new oilfields.

In addition, the three companies also stepped up oil exploration overseas last year. Among them, CNPC signed new contracts to jointly explore and tap oil and natural gas resources in some foreign countries.