In a face-to-face visit with hopes of putting meat on the bones after the historic summit between President Donald Trump and North Korean leader Kim Jong Un, U.S. Secretary of State Mike Pompeo spent two days in North Korea this week negotiating with counterparts.
After talks with the foreign ministers of Japan and South Korea on Sunday, the secretary of state said his efforts to press the North on nuclear weapons were legitimate.
Those include the formation of a working group to determine exactly how North Korea's denuclearization will be verified and a Thursday meeting with Pentagon officials to discuss the return of remains of American soldiers killed during the Korean War.
A letter from Kim to Trump was also delivered to Mr. Pompeo through Kim Yong Chol, a top North Korean party official and former spy agency chief, who with Mr. Pompeo played a key role in arranging the unprecedented summit in Singapore.
According to the spokesman, the North raised the issue of a possible declaration to formally end the 1950-53 Korean War, which concluded with an armistice and not a peace treaty, but the United States came up with a variety of "conditions and excuses" to delay a declaration.
He had said progress was made during his two-day visit to Pyongyang.
Some analysts think North Korea is trying to drag out talks in hopes that the USA will come around to accepting it as a nuclear weapons state, perhaps in a limited form that couldn't threaten the U.S. mainland directly.
In his assessment Mr Pompeo gave little away, but he said they had discussed at length a timeline for disarmament, including the destruction of a missile engine testing facility.
'The road ahead will be hard and challenging and we know critics will try to minimize what we have achieved, ' he said. The countries also agreed to create working groups that will be overseen by Sung Kim, the USA ambassador to the Philippines who has handled some lower-level discussions, to work out what State Department spokeswoman called the "nitty gritty details" of future talks.
It says pressure will remain until North Korea denuclearizes, but in statements this week, it redefined the USA goal as "the final, fully verified denuclearization" of the country. "Some places a great deal of progress".
Yesterday, Mr Pompeo appeared dismissive of these remarks, to the point of sounding slightly exasperated when questioned.
"The U.S. side came up only with its unilateral and gangster-like demand for denuclearization", the North Korean statement said.
Pompeo defended his position during the talks with North Korea, saying if his demands were "gangster-like" then the whole world is a gangster.
"So the work that we do, the path toward complete denuclearization, building a relationship between our two countries, is vital for a brighter North Korea and the success that our two presidents demand of us", Pompeo said.
"I have confidence that Kim Jong Un will honor the contract we signed &, even more importantly, our handshake".
The criticism, published on North Korea's government-run Uriminzokkiri website, said Washington should stop provoking the North with an "anachronistic human rights racket' at a time of diplomatic attempts to improve ties".