“Our nation will strongly call on major countries around the world to set aggressive goals,” added Hatoyama, 62, who last week suggested that Japan would seek a greater voice in international diplomacy.

Japan would present its target at international talks in Copenhagen in December aimed at agreeing a follow-up treaty to the Kyoto Protocol which expires in 2012.

Japan is the world’s number two economy and the fifth largest emitter of greenhouse gases, which are blamed for raising global temperatures, melting the earth’s ice caps and glaciers, and changing weather patterns.

“What we need in international negotiations is that politicians in the world assume responsibility in order to firmly prevent climate change and protect peace and stability at global levels,” Mr Hatoyama said.

The head of the Democratic Party of Japan made clear that Japan would ask other major emitters also to set tough targets, saying that “climate change cannot be stopped if only our country sets a reduction target”.

“A highly ambitious accord with participation by all major countries is a prerequisite to our country’s promise to the international community,” he said.

Without mentioning China or India by name, Mr Hatoyama said: “We think developing countries are also required to make an effort to reduce greenhouse gases, as a global effort is needed on the issue of climate change.”

“Developed countries should provide financial and technical support for developing countries that are trying to reduce greenhouse gases.”

In June, Mr Aso announced a far lower greenhouse gas reduction target, equivalent to eight per cent from 1990 levels by 2020, earning his government criticism from environmental groups.

Mr Hatoyama said: “I hope that a power shift in Japan will lead to a big change in climate change measures and mark the beginning of a big contribution to the future of our society in international negotiations.”