By contrast, Pompeo did suggest that the USA was prepared to make unspecified concessions to North Korean security concerns before the total dismantling of its nuclear program was achieved.
South Korean news agency The Chosunilbo reported that when Kim arrived in Singapore this week on an Air China Boeing 747, he also was accompanied by an IL-76 transport plane carrying food, "his bullet-proof limousine and a portable toilet".
Over the next few days, The Drum will bring you the latest on the summit with an industry perspective.
Later, Pompeo shared a picture of Trump speaking with the staff of the U.S. Embassy in Singapore.
As Trump was trying to build a bridge with Kim, he was smashing longtime alliances with Western allies with his abrasive performance at the G-7.
It's a dramatic departure for Trump, who kicked off 2018 bragging that his nuclear button is "much bigger" than Kim's.
The US-North Korean summit will mark the first-ever meeting of sitting leaders of the two countries.
Pyongyang's nuclear arsenal - which has seen it subjected to several sets of U.N. Security Council sanctions and threatened with military action by the Trump administration - will top the agenda. However, he took a U-turn soon and said the White House was proceeding with the preparations for the summit.More news: Putnam rips concealed weapons story, acknowledges failure to review background checks
Press secretary Sarah Huckabee Sanders, US Ambassador to the Philippines Sung Kim and National Security Council senior director for Asia Matt Pottinger will attend the working lunch.
Many questions remain unanswered, however, including whether the North Koreans have robust enough communication systems to make sure no one panics and launches an attack, said Vipin Narang, an associate professor at the Massachusetts Institute of Technology's Security Studies Program.
"I think the North will denuclearise ... because it knows it has no other alternatives", he said.
"North Korea has previously confirmed to us its willingness to denuclearize, and we are eager to see if those worlds prove honest", Pompeo said. The US president has also raised the possibility of further summits and an agreement ending the Korean War by replacing the armistice signed in 1953 with a peace treaty.
It was Kim's only foray on Monday outside of the St. Regis hotel, where he's been staying since his arrival a day earlier.
In return, Kim, said to be in his mid-thirties, called Trump "mentally deranged" and a "dotard".
Trump and Kim arrived in Singapore hours apart Sunday.
Trump, too, has recently sought to minimize expectations, saying additional meetings may be necessary. "I think I'll also know whether it will happen fast". Kim has sought to overhaul his image this year in a bid to ease worldwide sanctions imposed after he tested nuclear bombs and long-range ballistic missiles.
Sporadic provocations by the North have continued while Pyongyang has made increasing advances in its nuclear arsenal, which it says it needs to defend against the risk of a USA invasion.
While advisers say Trump has been reviewing briefing materials, the president insists his gut instincts will matter most when he gets in the room with Kim.