Thailand and Cambodia held talks on Thursday to open a border crossing as their conflict extended into a fourth day, with both countries still waiting to hear from U.S. President Donald Trump, who says he believes he can put a stop to the fighting.

Secretary of State Marco Rubio said the U.S. is “concerned” about a war that his boss claimed to have ended weeks ago. The Cambodia-Thailand conflict is one of several global conflicts President Trump has repeatedly claimed he ended in his second presidency,