An ex-U.S. ambassador to Korea says that North Korea will continue to use brinkmanship in an effort to get recognized as a nuclear power.

He predicted a bumpy road ahead for the six-way nuclear talks in persuading the North to agree to the verification of its nuclear disablement.

Alexander Vershbow made the comments in a keynote speech at a ceremony in Washington to mark both the establishment of the U.S.-based Korea Economic Institute and Korean American Day.

He said that getting the Korea-U.S. free trade deal ratified will be one of the main challenges facing the new U.S. administration.

But Vershbow added that in order to enjoy the many economic benefits the treaty has to offer, the two countries will have to find creative solutions to differences based on their history of friendly relations.