Negotiations

"I know my counterpart spoke with Chairman Kim during the course of our negotiations as well. We had productive, good-faith negotiations."

In practical terms, however, Pompeo mentioned only that officials from both sides would meet on July 12 as a working group to discuss the repatriation of the remains of some US soldiers killed during the 1950-1953 Korean War.

And he said some progress had been made towards agreeing "the modalities" of North Korea's destruction of a missile facility.

Saturday's talks were held at a villa in an official compound close to the imposing mausoleum where North Korea's former helmsmen Kim Il Sung and Kim Jong Il – the current leader's grandfather and father – lie in state.

As the day began, Pompeo left the compound to make a secure call to Trump away from potential surveillance, then returned to restart talks and they continued through a working lunch for almost six hours.

Pompeo, who was on his third visit to Pyongyang, began the outreach when he was still Trump's CIA director and remained the pointman on negotiations after the process became public and he became secretary of state.

In comparison to past international nuclear disarmament negotiations, the discussions between Washington and North Korea on thawing ties and dismantling the North's arsenal appear to be proceeding in reverse.

Rather than the two leaders crowning years of detailed negotiation with their one-on-one meeting, the short statement marked instead the start of a diplomatic long slog, and Trump earned the scorn of Korea watchers and non-proliferation experts when he declared the crisis over.

The task of establishing the disarmament programme now falls to Pompeo, who is seeking a formal declaration by the North of the size of its nuclear programme as well as an eventual timetable for it to be ended under international verification and inspection.