Beijing is believed to have granted Chinese companies the rights to conduct natural gas exploration in Japan's exclusive economic zone in the East China Sea, trade chief Shoichi Nakagawa said Sunday.

"We have obtained information" that natural gas development lots have been marked by China at "several locations within Japan's EEZ," the minister of economy, trade and industry said on a Fuji TV political talk show.

It is the first time information has surfaced on Chinese moves to carry out a gas project inside the Japanese zone.