The team, headed by Sung Kim, the State Department official in charge of Korean affairs, will stay in the Communist state for about a week and survey three key nuclear facilities, including the country's only operational 5-megawatt nuclear reactor, at Yongbyon, the South Korean agency said, citing officials.
"We expect the North's nuclear facilities to be disabled within the year," the agency quoted Kim as saying.
Pyongyang shut down the facilities, which also include a radiochemical lab and a nuclear fuel producing plant, earlier this year under a breakthrough deal in February with the United States, China, Russia, South Korea and Japan in exchange for aid and diplomatic incentives.
The visit comes following the latest round of six-nation talks in Beijing in late September, when the North agreed to disable its Yongbyon complex and declare full data on all its nuclear programs by the end of 2007.