Japan and China clarified their respective positions but were unable Thursday to agree on how to resolve their dispute over natural gas drilling in the East China Sea, where the two sides disagree over their exclusive economic zone boundaries.

During the one-day talks in Tokyo, Japan rejected China's proposal for joint development of two gas fields and China refused Japan's idea to tie up at four other sites, Japanese officials said.

Japan pointed out "problems" in the Chinese proposal, said Kenichiro Sasae, chief of the Asian and Oceanian Affairs Bureau at the Foreign Ministry who heads the Japanese team, but he would not give any details. "Now we understand what the Chinese side is thinking (about their proposals), but at the current stage, we cannot accept them," Sasae told reporters during a break halfway through the day. "Basically, what is important for us is that Japan's legal and economic rights are secured."