WASHINGTON (Kyodo) U.S. Treasury Secretary Timothy Geithner wants Japan to play an active role in the global economy when the Group of 20 leaders gather in London on Wednesday and Thursday.

The U.S. expects Asia's largest economy to play "a role commensurate with Japan's importance in the global economy," Geithner said in a briefing to journalists Monday ahead of the G20 summit of industrial and emerging countries.

Prime Minister Taro Aso is expected to announce during the summit a plan to boost aid to Asian economies by ¥500 billion, bringing Japan's total aid to the region to ¥2 trillion, government sources said.