The head of Central Intelligence Agency warned that a cash-starved and expansionist North Korea could sell its nuclear weapons and ballistic missile technology to other countries, including Iran, and that failure to halt such activity could trigger a global nuclear arms race.
"The logical next step will be to develop an arsenal of weapons", he said.
Mr Pompeo suggested that North Korea - which has a burgeoning nuclear programme but a faltering economy - may start selling its weapons to other countries.
"We are working diligently to keep them months away.it's not a static time frame", he said.
Pompeo's remarks came four days after the Wall Street Journal revealed that USA intelligence officials had gathered evidence of at least six Chinese ships entering ports in North Korea and transporting illicit cargo to Russian Federation and Vietnam in violation of United Nations sanctions against Pyongyang.
The CIA chief also noted that Kim appears to seek Korean reunification on his terms, not just protection of his regime, by pursuing the nuclear capability.
"We are taking the real-world actions that we think will make unmistakable to Kim Jong Un that we are intent on denuclearization".
Some are critical of the Trump administration for giving mixed messages on North Korea and for what some call "loose talk" on military options.
In interviews past year with Pompeo, Director of National Intelligence Dan Coats and National Security Agency Director Admiral Mike Rogers, Mueller's team focused on whether Trump had asked them to lean on former FBI Director James Comey, the sources said.
This plays into North Korea's perpetual demands for the United States to move its forces out of Korea and cease conducting joint military drills with South Korea, which the North denounces as dress rehearsals for an invasion. We're going to set the date, and we're not going to lose a thing.
"The differentiation lies in the confidence that he achieved full nuclear capability", he said, noting that Kim had emphasized the need for strategic weapons since he took power. "Our mission is to make the day that he can do that as far off as possible".
Mueller also asked the officials if Trump tried to shut down intelligence investigations into Russian election meddling and into contacts between Russian officials connected with President Vladimir Putin's government and associates of Trump or his campaign, the sources said on condition of anonymity.
"I am proudly saying that DPRK's nuclear force is capable of frustrating and countering any nuclear threats from the USA and it constitutes a powerful deterrent that prevents the United States from starting an adventurous war".