A South Korean nuclear envoy is to visit North Korea this week to discuss the possible purchase of unused fuel rods from its reactor, Yonhap news agency reported on Tuesday.
The agency, quoting a foreign ministry source, said deputy chief nuclear envoy Hwang Joon-Kook will leave for Beijing on Wednesday and fly to Pyongyang the following day.
Foreign ministry spokesmen could not immediately confirm the report.
"Hwang will visit Pyongyang and Yongbyon along with a group of related South Korean experts to examine the condition of the fuel rods," the source told Yonhap. "He will meet with some North Korean officials."
North Korea is disabling its plutonium-producing Yongbyon plants under a 2007 six-nation aid-for-disarmament pact. Removing the unused fuel rods would be one of the few remaining steps in the process.
South Korea has expressed interest in buying the rods for use at its nuclear power plants.
Hwang's trip, if confirmed, would indicate progress in disarmament moves and a possible improvement in inter-Korean relations.
The last six-nation talks in Beijing in December ended without agreement because of a dispute over ways to verify the North's declaration of its atomic activities.
The talks group the two Koreas, the United States, Russia, Japan and host China.
Inter-Korean relations have been frosty for months over the harder-line policy pursued by South Korean President Lee Myung-Bak.
The North has cut almost all official contacts with the South and on December 1 imposed tough curbs on border crossings.