Less than two months after a landmark U.S.-North Korea summit in Singapore, U.S. Secretary of State Mike Pompeo flew back to the city state on Friday and said North Korea’s continued work on weapons programs was inconsistent with its leader’s commitment to denuclearize, Reuters reported.

Pompeo was asked en route to Singapore about his statement in the U.S. Senate last month that North Korea was continuing to make bomb fuel and reports that North Korea, led by Kim Jong Un, was building new missiles.

“Chairman Kim made a commitment to denuclearize,” Pompeo told reporters. “The world demanded that they (North Korea) do so in the U.N. Security Council resolutions. To the extent they are behaving in a manner inconsistent with that, they are a) in violation of one or both the U.N. Security Council resolutions and b) we can see we still have a ways to go to achieve the ultimate outcome we’re looking for.”