Negotiations to end the border conflict, which has killed dozens of people since it began last week, are scheduled for Monday in Malaysia’s capital.

"The U.S. already flunked the test and that should be a wakeup call," a former senior U.S. State Department official told Newsweek.

At least eight civilians were killed in attacks in a disputed border area between Cambodia and Thailand on Thursday, according to authorities. Thailand said Cambodian soldiers opened fire on a military base in Surin.