A US source, who could not be identified as the schedule has not been announced, said Pompeo would invite Kim to an early lunch before the two likely head together to the White House, a short drive away.

Neither side has publicly announced the visit, with the US treading cautiously after Kim Yong-chol abruptly cancelled his last planned talks with Pompeo which were set for early November in New York.

But Trump has voiced optimism after receiving what he called a warm New Year’s letter from Kim Jong-un and has opined that the two leaders are “in love”.

Trump has repeatedly voiced eagerness to see Kim Jong-un again after their landmark June summit in Singapore, the first meeting ever between sitting leaders from the two countries that never formally ended the 1950-53 Korean war.

Tensions began to abate a year ago with the encouragement of South Korea’s dovish government. Trump has repeatedly hailed his diplomacy as a triumph, recently saying there would have been “a nice big fat war in Asia” if it were not for him.

He has said to expect an announcement soon about the second summit, with diplomats seeing Vietnam and Thailand as possible venues.

For Trump, the made-for-TV summitry with the young and elusive North Korean leader also offers a welcome respite from the steady negative headlines at home.

Special counsel Robert Mueller is probing whether Trump’s presidential campaign colluded with Russia, and his insistence that Congress fund a wall on the Mexican border has shuttered the US government for nearly a month.

For Kim, the stakes are more existential as he seeks guarantees of the survival of his regime.

Kim, backed by ally China as well as South Korea, is also hoping for an easing of international sanctions, but the United States insists on maintaining maximum pressure until Pyongyang moves forward on giving up its nuclear weapons.

In Singapore, Kim promised his “unwavering commitment to complete denuclearisation of the Korean peninsula.”

But the two sides appear to have different ideas on how to define that, with the United States expecting North Korea to give up nuclear weapons assembled over decades of work and Pyongyang more broadly seeking an end to what it sees as US threats.

“I think there is somewhat of a general consensus of what denuclearisation means. I think there is obviously still disagreement on how to get there – whether denuclearisation is the end of the process or the process itself,” said Jenny Town, managing editor of the 38 North website on North Korea policy at the Stimson Centre.

“Realistically, they can talk about it all they want to, they can define the end goal, but if you don’t have a common understanding of how to get there, you’re not going to reach that common goal,” she said.

She noted that Americans have traditionally preferred to hash out the details of agreements before big summits, while the type of leader-driven diplomacy favoured by Trump is more common in Asia.

“People have been very sceptical of this top-down approach, but we won’t know unless we try it,” she said.

Pompeo in a recent interview voiced hope at reaching a deal with North Korea that would “create a much better, safer America” but cautioned that it was unlikely to be finished during the next summit.