North Korean officials didn't show up Thursday for a planned meeting with U.S. counterparts to discuss returning the remains of American war dead, South Korean media reported, in the latest sign of tensions between the two sides.

U.S. negotiators arrived at the militarized border between the two Koreas, as had previously been announced by U.S. Secretary of State Mike Pompeo, and were kept waiting, the Yonhap News Agency reported, citing diplomatic officials it did not identify. The meeting had been expected to be the first working-level talks between the two sides since Pompeo's visit to Pyongyang ended Saturday with North Korea denouncing the U.S.'s "unilateral and gangster-like demand for denuclearization."

A spokesman for U.S. Forces Korea referred questions Thursday to the Department of Defense in Washington. The Pentagon did not respond to repeated requests for comment Wednesday. Pompeo had said when announcing the talks that the meeting could "move by one day or two."