U.S. Deputy Secretary of State Stephen Biegun is due to visit South Korea next week to discuss stalled talks with North Korea.

The activists have sent leaflets and plastic bottles filled with rice across the border, prompting North Korea to raise provocations with the South.

North Korea abruptly used Park Sang-hak's leaflet campaign as a justification for a series of provocative steps against South Korea.

It was not immediately clear why North Korea had softened its position, which came after it blew up a liaison office last week and cut off communication hotlines with the South.

The move is certain to intensify tensions between the Koreas, after the North abruptly raised its rhetoric against South Korean civilian leafleting and pushed to resume its psychological warfare against the South.

Wreaths were laid and the call of a single bugle rang out near Parliament Hill this morning as a subdued ceremony was held to mark the 70th anniversary of the start of the Korean War.

The announcement came a day after North Korea destroyed an inter-Korean liaison office in a choreographed display of anger that puts pressure on Washington and Seoul amid deadlocked nuclear diplomacy.

The General Staff of the Korean People's Army said it's reviewing a ruling party recommendation to advance into unspecified border areas that had been demilitarized under agreements with the South.

An official said the North would never again gift Trump with high-profile meetings and concessions unless it gets something substantial in return.

The United States should "hold its tongue" and address its own domestic problems unless it wants to "experience a hair-raiser," an official said.