Washington (CNN) President Donald Trump's national security adviser John Bolton said on Monday that the administration does not feel North Korea is living up to its end of an agreement to denuclearize.

The comments from Bolton came as Secretary of State Mike Pompeo has been stressing the process will take time, revealing a possible split within the administration over how to handle Pyongyang.

"We're waiting for the North Koreans to begin the process of denuclearization, which they committed to in Singapore and which they've not yet done," Bolton told CNN the same day.

Bolton also stressed in the CNN interview that Trump had been willing to have a dialogue with North Korea and likened the US approach to North Korea with its pressure on Iran.

"Maximum pressure on both governments to give up their pursuit of deliverable nuclear weapons, but a willingness to talk to their leaders to see if there's a way out," Bolton said.

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