Chinese Foreign Ministry. When asked about China’s position as Cambodia and Thailand have recently expressed positive intentions to cease fire and end the conflict under the med

The Thai warning came as the U.S. expressed its grave concern about the most serious fighting in years between the Southeast Asian neighbors. The U.S. and China compete for influence in fast-growing Southeast Asia, and both have good relations with Thailand and Cambodia.

The fighting intensified and spread to new areas despite international calls for a ceasefire. Read more at straitstimes.com. Read more at straitstimes.com.

Thailand, bound to America by a treaty from 1954, appears so far to have the upper hand against Cambodia after air strikes by American-made F16 fighters. Undaunted, however, the Cambodians, armed with Chinese-made rifles,

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

Bangkok and Phnom Penh have been fighting over territory disputed since colonial power France drew the border between them more than a century ago.

Of course, trouble at the 508-mile (817 km) shared border is nothing new. For over a century, Thailand and Cambodia have contested sovereignty at various undemarcated points in the thick jungle punctuated with culturally-significant temples albeit with scant strategic or economic value.

Tensions along Cambodia's northern border with Thailand have been simmering since May, when a Cambodian soldier was killed in a clash with Thai forces.

China has blamed “Western colonialists” for ongoing clashes on the Thai-Cambodian border that have left at least 15 people dead and forced tens of thousands to flee their homes.