"We hope to establish a project such as an emissions-right exchange in the later half of the year," said an official with the state-run JBIC. But the group is still agreeing on the details.

"We still need further analysis on issues such as government involvement and assessment of potential participants," the source told AFP on condition of anonymity.

She said the market would reduce Japan's dependence on the European Union's Emissions Trading System, which has become the world's major exchange for carbon credits.

"With the project, we hope to stimulate emission rights trading in Japan," she said.

According to the Nikkei business daily, the new Japanese exchange would welcome Chinese, US and other foreign companies, as domestic power companies and steelmakers are eager to buy their emissions allowances. Japan's greenhouse gas emissions rose 8% in 2005, while the country is obligated - through the Kyoto agreement - to reduce its average annual emissions for 2008 through 2012 by 6% compared with 1990 levels.

Japan is a major buyer of world carbon, purchasing nearly 30% of the world's carbon credits between January 2005 and September 2006, more than any other country, the Nikkei said.