A top U.S. official says inter-Korean ties must be improved in order to resume the six-party nuclear talks.

Assistant Secretary of State for East Asian and Pacific Affairs Kurt Campbell spoke at an Obama administration Asia-Pacific policy forum hosted by the U.S. Institute of Peace.

He said the U.S. is ready to sit at the negotiating table with North Korea and other participating nations if the appropriate environment is fostered.

Campbell said ties between the two Koreas must improve following the sinking of a South Korean warship and he called on North Korea to sincerely pursue denuclearization.

His remarks suggest that an improvement in South-North relations is a precondition for resuming the six-way talks.