U.S. Secretary of State Marco Rubio spoke with the foreign ministers of Cambodia and Thailand on Sunday, urging them to immediately deescalate tensions and telling them the United States was ready to help with talks, the State Department said.

"The United States is prepared to facilitate future discussions in order to ensure peace and stability between Thailand and Cambodia," the department said in statements on Sunday about separate calls with Thai Foreign Minister Maris Sangiampongsa and Cambodian Foreign Minister Prak Sokhonn.