The leaders of Cambodia and Thailand have agreed to meet to negotiate a ceasefire, according to a social media post by United States President Donald Trump on Saturday.

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.

Thailand warned its conflict with neighboring Cambodia could “potentially develop into a war” as troops used rockets and artillery to shell targets along their contested border for a second

BANGKOK -- Thai and Cambodian leaders will meet in Malaysia for talks to end hostilities, a spokesperson for the Thai prime minister’s office said Sunday. This comes following pressure from U.S. President Donald Trump to end a deadly border dispute, now in its fourth day, which has killed at least 35 people and displaced more than 218,000.

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

Thailand and Cambodia clashed for a fourth day on Sunday, despite US President Donald Trump warning them they are risking potential trade deals with the US. The US president said on Saturday the leaders of the two countries had agreed to meet to negotiate a ceasefire.

At least 16 people have been killed and tens of thousands have been displaced as fighting extended to a second day.

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

China will continue to play a “constructive role” in helping to ease regional tensions, Foreign Minister Wang Yi said on Friday, as Thai and Cambodian troops exchanged fire on their border for a second day.