Mike Pompeo
Mike PompeoReuters

US Secretary of State Mike Pompeo said he had a "very positive" meeting with North Korea's foreign minister on Wednesday and will visit Pyongyang again next month to prepare for a second summit between President Donald Trump and North Korean leader Kim Jong Un, NBC News reported.

Pompeo wrote on Twitter that his meeting with Ri Yong Ho on the sidelines of the United Nations General Assembly in New York was to discuss the summit and "next steps toward denuclearization of #NorthKorea."

"Much work remains, but we will continue to move forward," Pompeo added.

The State Department later said Pompeo accepted an invitation from Kim to visit Pyongyang next month, for what will be his fourth visit this year.

Trump recently called off a planned trip by Pompeo to North Korea, and explained that Pyongyang was slow-walking efforts to dismantle its nuclear program.

During a June summit in Singapore, Trump and Kim signed an agreement which includes a commitment to achieve total denuclearization of Korea, with promises to pursue “vigorous negotiations” to that end.

Subsequent reports suggested that despite its commitment to denuclearize, North Korea has continued to expand infrastructure at nuclear and missile sites.

Even after he called off Pompeo’s previous visit to Pyongyang, Trump insisted the United States is “doing well” in its diplomatic efforts with North Korea.

Trump said on Wednesday the United States and North Korea had "a wonderful relationship going" and he would announce the timing and location of his next meeting with Kim in the "very near future."

Trump, asked as he entered the United Nations what North Korea had to do before a second summit, said there had been "a tremendous amount of progress" since last year, and added, "They're denuclearizing North Korea."

In his address to the UN General Assembly on Tuesday, Trump praised Kim for his courage in taking steps to disarm, but said much work still had to be done and sanctions must remain in place on North Korea until it denuclearizes.