Pompeo credited US President Donald Trump with leading the international "pressure campaign" of sanctions against North Korea to achieve the "first significant diplomatic breakthrough in decades" through his summit with North Korean leader Kim Jong-un in June.

At that Singapore meeting, Kim committed to work toward complete denuclearization of the Korean Peninsula in exchange for security guarantees from the US The two leaders also agreed to work to establish "new" relations between their nations.

"We must not forget what's brought us this far: the historic international pressure campaign that this council has made possible through the sanctions that it imposed," Pompeo said. "Until the final denuclearization of the DPRK is achieved and fully verified, it is our solemn collective responsibility to fully implement all UN Security Council resolutions pertaining to North Korea."

DPRK stands for North Korea's official name, the Democratic People's Republic of Korea.

Last year the Security Council unanimously adopted multiple sanctions resolutions in response to North Korea's nuclear and ballistic missile tests to choke off sources of revenue for the regime.

Pompeo said some of those sanctions have been violated, including through ship-to-ship transfers of refined petroleum to North Korea and continuing hiring of North Korean laborers overseas.

"Enforcement of UN Security Council sanctions must continue vigorously and without fail until we realize the fully, final, verified denuclearization," he said. "The members of this council must set the example on that effort, and we must all hold each other accountable."

Pompeo plans to travel to Pyongyang next month to set up a second summit between Trump and Kim.

On Wednesday he met with North Korean Foreign Minister Ri Yong-ho in New York to discuss planning for the summit and denuclearization efforts.

"We are well into a diplomatic process, and we hope -- indeed, we want -- to see this through to a successful end," Pompeo said.

"President Trump has made abundantly clear that if Chairman Kim follows through on his commitments, a much brighter future lies ahead for North Korea and its people, and the United States will be at the forefront of facilitating that bright future."

But if North Korea does not denuclearize, he warned, it will face "ever-increasing isolation and pressure." (Yonhap)