Seoul - North Korea on Thursday said there had been "progress" in its latest talks with the United States in the dispute concerning the North Koreans' nuclear activities, according to reports in the South Korean capital Seoul.

A Foreign Ministry spokesman in Pyongyang was quoted by the official KCNA news agency as commenting that "the negotiations proceeded in a sincere and constructive manner, and progress was made" in the talks.

The US delegation, led by Sung Kim, director of the US State Department's Office of Korea Affairs, in the meantime has returned to Seoul after crossing the heavily-fortified inter-Korean border Tuesday to travel to Pyongyang.

The spokesman said the talks concerned the issues pertaining to the agreement on North Korea declaring its nuclear activities. But he gave no further details.

The US delegation had also included officials from the National Security Council and Defence and Energy departments, the embassy said.

The visit to Pyongyang came after North Korea's and the United States' top nuclear negotiators met two weeks ago in Singapore. They both spoke of making progress although a breakthrough wasn't achieved on the declaration, the current sticking point of six-nation talks aimed at ending North Korea's nuclear programmes.

The United States insists North Korea has failed to fulfil its promise to submit a complete declaration. However, US newspaper reports last week indicated that the United States was prepared to relax demands that North Korea admit to a uranium-enrichment programme and to offering nuclear assistance to Syria.

The issue has stalled the six-nation talks involving North and South Korea, the United States, China, Japan and Russia since the end of last year. As part of those talks, Pyongyang agreed to declare its nuclear programme and dismantle its nuclear facilities in return for energy and economic aid. (dpa)