Washington has told Tokyo of its plan to beef up its military presence in Japan to prepare for a possible emergency amid rising tensions on the Korean Peninsula, it was learned Sunday.

The buildup includes F-15 fighter bombers and U-2 reconnaissance aircraft, according to sources.

Tokyo has welcomed Washington's plan, citing "the need for deterrence under the Japan-U.S. security arrangement in the Asia-Pacific region to remain effective" even if the U.S. attacks Iraq, the sources said.