The Cabinet failed to reach a consensus Friday on a national midterm emissions reduction target, despite Prime Minister Taro Aso's plan to announce it next Wednesday.

The main differences emerged between the Environment Ministry's hope to set an ambitious target and the Ministry of Economy, Trade and Industry's aim for a lower target.

"There were differences of opinion between the ministers. I candidly think that we need to make efforts to put them together," Environment Minister Tetsuo Saito told a news conference, saying he conveyed his view that a cut of 15 percent to 25 percent by 2020 from 1990 levels would be desirable.

Minister of Economy, Trade and Industry Toshihiro Nikai told reporters, "I asserted that it would not be appropriate to impose a tremendous figure on people by turning to an idealistic theory."

Chief Cabinet Secretary Takeo Kawamura said, "Though we have to take both views into consideration, we naturally have to think about moving in a direction that is ambitious and exercising our leadership in curbing global warming."

Kawamura told a news conference that the participants did not reach consensus over which direction to take.

But they agreed to set the base year for calculating emissions at 2005 in setting the target for 2020, the top government spokesman said.

The participants also shared the view that the United States, China and India, which did not participate in the 1997 carbon-capping Kyoto Protocol, should participate in a new carbon-capping framework to succeed the protocol after it expires in 2012, according to Kawamura.

The meeting was also attended by Finance Minister Kaoru Yosano and Foreign Minister Hirofumi Nakasone.

A government study panel has presented six options for Japan's greenhouse gas emissions target for 2020, ranging from a 4 percent increase to a 25 percent cut from 1990 levels.