Updated

A State Department (search) adviser on North Korean (search) issues has taken the unusual step of resigning shortly before six-nation talks in China on the communist country's nuclear program.

State Department spokesman Philip Reeker (search) disclosed Monday the departure of Charles "Jack" Pritchard and said he was taking a job in the private sector. He said Pritchard's resignation, which took effect last Friday, was not based on policy disagreements.

Pritchard often acted as liaison with North Korean officials, frequently flying to New York to confer with the country's U.N. diplomats.

Reeker said Pritchard had a distinguished career in government that included service in the military and the State and Defense departments. He added that Secretary of State Colin Powell (search) expressed appreciation for Pritchard's services.

Pritchard's resignation has been in the works for months, Reeker said.

On Wednesday, the United States will join the two Koreas, China, Japan and Russia for three days of talks on North Korea's nuclear program.