North Korea is continuing to produce fuel for nuclear bombs in spite of its pledge to denuclearize, U.S. Secretary of State Mike Pompeo said Wednesday, even as he argued that the Trump administration was making progress in talks with Pyongyang.

Asked at a Senate Foreign Relations Committee hearing whether North Korea was still making bomb fuel, Pompeo responded to Democratic Sen. Ed Markey by saying: "Yes, that's correct. ... Yes, they continue to produce fissile material."

Pompeo declined to respond when asked whether North Korea was continuing to pursue submarine-launched ballistic missiles or whether its nuclear program was advancing generally.