In December this year, parties to the United Nations Framework Convention on Climate Change (UNFCCC) will descend on Copenhagen to wrangle over the details of a new global climate deal — a potential successor to the Kyoto Protocol. See Nature’s Road to Copenhagen special for more coverage.

Japan’s new ruling party has warned that its election pledges on climate change are contingent on other countries’ moves.

Before the recent election in Japan, the Democratic Party of Japan was calling for a cut in greenhouse-gas emissions to more than 25% below 1990 levels by 2020 (see: Japan election sparks science pledges).

Now Katsuya Okada, the party’s secretary-general, has told Reuters, “This is not something Japan will do on its own. The premise is an agreement that includes other countries such as China and India.”

Okada dodged the question of whether the DJP would change its target if an international agreement couldn’t be reached. “We are trying to reach an agreement so we are not discussing what to do in the absence of an agreement,” he said.

Japan’s largest business group, Keidanren, has already come out against the 25% target (Yomiuri Shimbun, via Reuters).

Okada’s caveat of the party’s target may also deflate some of the hopes about the DJP’s climate stance, which was noticeably tougher than their rival Liberal Democratic Party.

Earlier this week – after the election but before the Reuters interview – Andreas Carlgren, Sweden’s environment minister said of the target, “That could create momentum in the climate-change negotiations. That is very close to the European ambitions.” (Bloomberg.)