U.S. Secretary of State Mike Pompeo said Thursday that economic sanctions on North Korea will not be lifted until the time the U.S. has the capacity to verify the North's elimination of its nuclear program.

He told an interviewer that real progress has been made on North Korea but "there still remains an awful lot of its nuclear program that needs to be dismantled and verified." 

He said the U.S. is working to bring those steps forward, and stressed the importance of verification. 

China, Russia, and South Korea are calling for an easing of sanctions as a corresponding measure to the dismantlement of nuclear facilities in Yongbyon.