A new South Korean nuclear negotiator is on his way to the United States to meet officials and coordinate policy on North Korea's nuclear programs.

Officials said Lim Sung-nam departed for Washington Thursday, a day after being appointed to replace Wi Sung-lac as Seoul's chief delegate to six-nation talks on Pyongyang's programs. Wi was named ambassador to Russia in what the foreign ministry described as a routine re-shuffle.

Officials said Lim will brief American officials on a recent round of talks in Beijing between nuclear negotiators for North and South Korea. They said the three-day visit will also deal with preparations for a visit to Washington next week by South Korean President Lee Myung-bak.

Before flying from Seoul, Lim told South Korea's Yonhap news agency that he will try to encourage North Korea to give up its nuclear programs by closely coordinating with the United States.

South Korean officials insisted that Wi's replacement with Lim — a former deputy chief envoy to the talks — did not reflect a change in policy. However it comes just a month after Mr. Lee named a new unification minister to handle relations with the North. The new minister is considered less hostile to Pyongyang than his predecessor.

The six-party talks — involving the two Koreas, the United States, China, Russia and Japan — have been stalled since Pyongyang abandoned the process in April 2009 and staged a nuclear test weeks later.

In recent months, North Korea has been seeking an immediate resumption of the disarmament talks, which could provide it with economic and diplomatic benefits. The request has sparked a flurry of diplomatic engagements, but Seoul and Washington say formal talks cannot resume until the North shows its commitment to ending its rogue nuclear weapons program.