Thailand and Cambodia reaffirmed their shaky ceasefire violation after days of fighting along their border, as China stepped into negotiate with the two countries.

Thailand’s military accused Cambodian forces on Wednesday of breaching a ceasefire agreement at three separate locations along the disputed border, warning that continued aggression could compel Thai forces to respond more decisively.

Cambodia and Thailand each said the other had launched artillery attacks across contested border areas early on Sunday, hours after U.S. President Donald Trump said the leaders of both countries had agreed to work on a ceasefire.