Japan's new leader has promised a big cut in greenhouse gas emissions, saying he will aim for a 25% reduction by 2020 compared to 1990 levels.
Yukio Hatoyama is due to take over as prime minister on 16 September, after a resounding election victory in August.
The BBC reports Mr Hatoyama's announcement is part of his Democratic Party's assertive policy on green issues.
His predecessor, Taro Aso, had pledged cuts of only 8%.
Japan is the world's second-largest economy and fifth-largest emitter of greenhouse gases, which are a major contributor to global warming.
The plans have already sparked resistance from business groups in Japan, with parts of the automotive industry expected to lobby against tough emissions targets.
Japan will present its new target at climate talks in Copenhagen in December.