The declaration from Trump comes after he said over the weekend that he had spoken to the leaders of Cambodia and Thailand, urging a ceasefire, adding the U.S. would not get back to the "trading table" with the southeast Asian countries until fighting stops.

Thailand and Cambodia reaffirmed their shaky ceasefire on Wednesday after China helped mediate a peace process to end days of border fighting. The ceasefire reached in Malaysia was supposed to take effect at midnight on Monday,