SEOUL, South Korea — North Korea on Friday withdrew its staff from the joint liaison office it has operated with South Korea since September, signaling a hardening of its position toward the South weeks after the failed summit meeting between the North’s leader, Kim Jong-un, and President Trump.

North Korean staff at the liaison office in Kaesong, a North Korean town just north of the two countries’ border, packed up and left on Friday, saying they had been ordered to do so, the South’s Ministry of National Unification said. They did not ask their South Korean counterparts to leave, the ministry said.

“We consider the North Koreans’ decision regrettable and hope that they will return as early as possible so the liaison office can resume its normal operation,” the ministry said in a statement.

It was the North’s latest show of discontent since the talks in Hanoi, Vietnam, between Mr. Kim and Mr. Trump over the North’s nuclear arms program ended without a deal. North Korea blamed what it called “an atmosphere of hostility and mistrust” created by Washington for the breakdown in negotiations.