SEOUL (Reuters) - North and South Korea held their first three-way talks with the United Nations Command (UNC) on Tuesday to discuss ways to demilitarize the border as the neighbors push for peace, South Korea’s defense ministry said.

FILE PHOTO: North Korean leader Kim Jong Un and South Korean President Moon Jae-in talk while taking a walk at Samjiyon Guesthouse in Ryanggang province, North Korea, September 20, 2018. Pyeongyang Press Corps/Pool via REUTERS

The two Koreas agreed this week to begin reconnecting rail and road links, in spite of U.S. concerns that a rapid thaw in relations could undermine efforts to press North Korea to give up its nuclear weapons.

Tuesday’s meeting followed a North-South summit last month at which the Koreas agreed to hold talks with the U.S.-led UNC, which oversees affairs in the Demilitarized Zone separating the two Koreas, to smooth the way to disarming one of the world’s most heavily fortified frontiers.

The meeting at the border village of Panmunjom on Tuesday lasted about two hours and was led by military officials of the rank of colonel from the two sides and Burke Hamilton, secretary of the UNC Military Armistice Commission, the ministry said.

“They discussed practical issues regarding demilitarization steps to be conducted in the future,” the South Korean ministry said in a statement.

The steps they are aiming for range from withdrawing firearms and guard posts to reducing personnel and adjusting surveillance equipment, the ministry said, adding that the three-way channel would be used for more discussions.

U.S. General Vincent Brooks, who leads the United Nations Command, said the talks were designed to use existing means of managing issues along the DMZ to try to achieve the goals set out by the two Koreas.

“I am encouraged by this productive, trilateral dialogue,” Brooks said in a statement. Future meetings would move on to tackle the steps the two sides had set out, he said.

Despite this week’s talks, North Korea has sounded some sour notes, blaming Seoul for delays in implementing agreements and denouncing the United States for insisting that international sanctions must stay in place until Pyongyang gives up its nuclear weapons.

A commentary on the official North Korean news agency KCNA on Tuesday said this amounted to a “barbarous strangling” of North Korea and it would be difficult to make “even an inch” of progress in talks while sanctions remained in place.

The commentary also took a swipe at U.S. President Donald Trump, saying he had “bragged” of big progress after his June summit with North Korean leader Kim Jong Un and questioning what this meant if a hostile policy remained in place.

The U.S. State Department reiterated the tough U.S. stance on Tuesday.

“President Trump has been very clear that sanctions relief will follow denuclearization, and the sooner we get to that point the sooner we can lift sanctions,” a spokeswoman said.

She said the U.S. special representative for North Korea, Stephen Biegun, held talks with Russian Deputy Foreign Ministers Igor Morgulov and Sergei Ryabkov in Moscow on Tuesday and emphasized “the need to continue fully coordinated communication to ensure that denuclearization proceeds as quickly as possible.”

Biegun is also due to visit Brussels and Paris for talks with EU, NATO, and European counterparts.

North Korea and the rich, democratic South are technically still at war because the 1950-53 Korean War ended in a truce, not a peace treaty.

South Korean President Moon Jae-in has been keen to agree a declaration formally ending the war by the year-end, but Washington has linked this to progress on denuclearization.

North and South Korea are looking to pull out 11 guard posts within 1 km (0.6-mile) of a Military Demarcation Line on their border by the end of the year.

They began removing land mines in several small areas this month and will build roads for a pilot project set for April to excavate the remains of soldiers missing from the Korean War.

Both sides also plan to withdraw all firearms from a Joint Security Area at Panmunjom, cut to 35 each the numbers of personnel stationed there and share information on surveillance equipment.