has started collecting information on the program and will decide by year's end whether to accept the request, the officials said.

Senior agency official Kiyoshi Higuchi hinted that the agency is willing to participate in the basic development plan, which will start in January.

The European Space Agency is also mulling a role in the project, and Japan's participation would enable Russia, Japan and European nations to operate an international space station without relying on the United States.

NASA has said it will retire the space shuttle by 2010; it plans to send astronauts back to the moon by 2018 in a vehicle designed to replace the space shuttle.

"We should not rely on only one system to transport, and it is desirable to have alternative measures for stable space activities," Higuchi said.

Russia has told JAXA that the Kliper, a successor to the Soyuz spacecraft, will be able to accommodate six astronauts, up from three for the Soyuz, and allow them to be in space for about 10 days, the officials said.

The new spacecraft is chiefly designed to transport people to and from a space station, while being used also for scientific purposes and space tourism.

Russia has also told the Japanese agency that the development of the Kliper will cost only about 100 billion, yen they said.