The United States says it is deeply concerned about the tide of violence along the border between Thailand and Cambodia.
Renewed fighting has broken out near two contested temples in the Khmer region, killing 13 soldiers.
US Secretary of State Hillary Clinton has said the loss of life, displacement of civilians and damage to property is regrettable, and has called for Thailand and Cambodia to exercise restraint.
The Obama administration is looking to the regional grouping ASEAN and its current chair, Indonesia, to foster a resolution to end the fighting.
But Thailand has rejected any third-party intervention, saying the two parties need to work their border issues out for themselves.
Tens of thousands of civilians have been forced to flee their homes on both sides as heavy weapons fire pounded the jungle frontier, shattering a fragile ceasefire that had held since February.