Japanese and Chinese firms from the energy sector signed cooperation agreements Thursday, a sign that they may develop more oil and gas projects together in the near future.

Six deals were signed at the start of the Japan-China energy cooperation seminar Thursday, held as part of Chinese Premier Wen Jiabao's visit here.

"This dialogue between Chinese and Japanese companies will create a lot of businesses opportunities, and we welcome Japanese companies to come and do business in China," Ma Kai, head of China's National Development and Reform Commission, said in his opening address to the group.