"Russian specialists are preparing to fly to North Korea to monitor the progress on closing down their nuclear facilities," a diplomat said.
Technical experts from the United States, also party to the six-nation nuclear disarmament process, are already at Yongbyon, leading a team which is dismantling the country's nuclear program.
The spokesperson said the visit is in line with agreements the six nations reached October 3 that North Korea decommissions three facilities at the Yongbyon center, about 100 km (62 miles) north of Pyongyang.
In a joint statement published on October 3 following the negotiations, North Korea agreed to decommission its nuclear facilities at Yongbyon, including a 5 MW nuclear reactor, a radiochemical lab and a nuclear fuel processing plant by December 31.
The representative said the expert's visit is in line with preparations for a meeting of negotiators in Beijing, scheduled for December 6 through 8, which will assess Pyongyang's denuclearization progress and consider holding talks at the level of foreign ministers.
North Korea, which tested a nuclear bomb in October 2006, closed down its main nuclear reactor in July under a February six-party deal.
In return for its cooperation, North Korea is to receive aid equivalent to one million tons of fuel oil, and the U.S. has promised it will take steps to remove the country from its blacklist of countries suspected of aiding terrorism.
The six-party talks were first held in August 2003.