In this photo taken on Monday, April 23, 2012, North Korean soldiers stand guard on the demarcation line of the Demilitarized Zone that separates the two halves of the Korean peninsula at Panmunjom, North Korea. (AP Photo/Vincent Yu)

North and South Korea opened their first official talks in two years on Sunday at a border village "without argument", the South said, building on an easing in tensions from nearly daily threats two months ago of impending nuclear war.

The meeting in Pammunjon, where the armistice was signed in the 1950-53 Korean War, was taking place hours after U.S. President Barack Obama and Chinese leader Xi Jinping agreed at a summit that the North had to abandon its nuclear program.