Both sides are finalising preparations for Tuesday's historic forum in Singapore, which is due to kick off at 9:00am (local time).
He said that those talks "in fact are moving quite rapidly and will come to a logical conclusion more quickly than anticipated".
The foreign minister of Singapore tweeted out a picture of the cake presented to Trump at the luncheon today in Singapore.
The roads are blocked off along the routes Kim and President Trump will travel. Again accusing the longtime United States ally of unfair trade practices, Trump added: "Then Justin acts hurt when called out!"
There was speculation throughout the day over whether Kim Jong Un had taken his private jet- an Ilyushin IL-62M - from Pyongyang, but official photos released by the Singaporean Ministry of Communications and Information showing Kim meeting Balakrishnan on the tarmac appear to reveal that he flew to Singapore aboard an Air China Boeing 747.
Pompeo also said that Trump had called Japanese Prime Minister Shinzo Abe and South Korean president Moon Jae-in.
Not a personal insult, but one of the most intimidating of Trump's threats came in August after USA media reported Pyongyang had successfully miniaturised a nuclear warhead to fit into a missile.
And until denuclearisation takes place, sanctions against North Korea would remain in place, he stressed.
"I'm very optimistic that we will have a successful outcome from our meetings tomorrow", he said.
Image Kim Yo Jong also enjoyed a walkabout in Singapore
Choi Ho-chul, a 73-year-old former bank employee, said he doubts the North would give up nuclear weapons, which he said were a "means to control its population".
Kim is expected to stay at the St Regis hotel and Trump at the Shangri-La, both in the Tanglin area in downtown Singapore.
"It's unknown territory in the truest sense but I really feel confident", Trump said.
The president is accompanied by Secretary of State Mike Pompeo - who has visited Pyongyang twice to prepare for the summit - and National Security Advisor John Bolton, a hardliner on dealing with North Korea.
In his "dotard" statement in response to Trump's United Nations speech, Kim also said: "A frightened dog barks louder".
"Despite his young age, he seems to be shrewd", he said, adding that he believes Kim realises his crusade to develop a nuclear arsenal to ensure his regime's survival has "hit a dead end" under intensifying sanctions.
That could precede a full treaty which would raise complex issues needing extensive negotiation, and would need to involve China, which backed the North during the conflict and is a signatory to the armistice.
Singapore is one of the few countries that have diplomatic relations with both the U.S. and North Korea.
"Wide-ranging and profound views on the issue of establishing new DPRK-US relations, the issue of building a permanent and durable peace-keeping mechanism on the Korean peninsula, the issue of realising the denuclearisation of the Korean peninsula and other issues of mutual concern, as required by the changed era, will be exchanged at the DPRK-US summit talks", the Korean Central News Agency (KCNA) reported in English.More news: Kindergarten lockdown poem hanging inside classroom upsets parents
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