President Heads to Asia

WASHINGTON (AP) -- President Barack Obama is heading to Asia, where countries are keeping close watch on the crisis in Ukraine amid territorial tensions with China.

Obama leaves Washington on Tuesday and is set to visit Japan, South Korea, Malaysia and the Philippines.

Each country has a dispute with China over islands in the South and East China Seas. Their leaders will be trying to get a sense of Obama's willingness to support them if the conflicts boil over.

U.S. officials have taken a tougher line on the territorial issues in recent weeks. They've warned China against the use of military force and noted that the U.S. has treaty obligations to defend Japan.