'The U.S. president and vice president don't generally travel on the same plane, ' he said.
It formally referred to Trump by his full name in the Monday report, including his middle initial - the first time it has done so.
Outside the Istana, the presidential palace where Trump met Singaporean Prime Minister Lee Hsien Loong, well-wishers displayed American flags and a boy held up a sign reading: "I love President Trump!".
But he has since lowered expectations, backing away from an original demand for North Korea's swift denuclearization. He released a photograph from inside the room of North Korean vice foreign minister Choi Sun-hee smiling across the table at the United States lead negotiator, the Philippines ambassador Sung Kim.
Chairman Kim yesterday held a meeting with Prime Minister Lee.
During the meeting, the officials also celebrated Trump's birthday.
Prime Minister Lee wished Kim a success for the summit and expressed hope that the US-North Korea meeting will advance the prospects for peace and stability in the Korean peninsula and the larger region.
Richard Haas, president of the Council on Foreign Relations think-tank, said the G7 meltdown had put more pressure on Trump to cut a deal with the nuclear-armed Kim. He told reporters at a news conference on Monday: "We are hopeful the summit will have set the conditions for future productive talks".
Trump had said that he would know "within the first minute" of meeting Kim whether or not the North Korean leader was serious about the nuclear negotiations.
Trump insisted last week that the summit will "not be just a photo op", saying it will help forge a "good relationship" that would lead to a "process" toward the "ultimate making of a deal".
Late on Monday. Trump phoned Moon from Singapore.
But the spectacle was absorbing.
Security was also tight outside the Shangri La Hotel, where Trump is expected to stay.
Similar scenes were seen on Sunday when Kim and Trump arrived in the city, and when Kim went to meet Lee.
Yellow barricades line the roads on Sentosa island.
Tuesday's meeting will be the first time a serving United States president has sat down with the leader of North Korea, and comes just months after fears of conflict soared as the two traded personal insults and threats of war.
On the streets, Kim and Trump impersonators thrilled around 100 fans who paid $10 to take selfies at Bugis Junction mall at the weekend.
Lee said the cost was worthwhile.
Kim seeks relief from crippling economic sanctions imposed by the global community, a non-aggression pact that would guarantee his regime's security, normalization of relations and the eventual removal of the roughly 30,000 US troops from South Korea.
Likely to attend the summit with Trump are Pompeo, Bolton and White House chief of staff John Kelly.
This gives him a massive advantage over Trump, who has a maximum of eight years, and means Kim can play the long game.
Former US ambassador to Russia Michael McFaul summed it up: "If Trump can't negotiate a deal on milk with one of our closest allies, how is he going to get a deal on nuclear disarmament with one of our greatest foes?"
Last year it carried out by far its most powerful nuclear test to date and launched missiles capable of reaching the USA mainland, sending tensions soaring to a level unseen in years as a newly-elected Trump traded threats of war and colorful personal insults with Kim, with Trump dubbed a "dotard" and Kim "Little Rocket Man".