Trump thanks Singaporean leader for hosting summit with Kim

President Donald Trump expressed optimism about Tuesday's meeting during a working lunch with Singapore's Prime Minister Lee Hsien Loong and aides to both leaders.

Trump says he thinks "things can work out very nicely" with North Korea on the eve of his historic summit with Kim Jong-un.

He also told Lee the decision to hold the summit in the island city-state of Singapore was "made very consciously" and offered thanks.

"We appreciate your hospitality and professionalism and your friendship," the US president added. 

"Great to be in Singapore, excitement in the air!" he tweeted on Monday.

North Korean and US negotiators also met in Singapore for final preparations on the eve of the unprecedented summit.

Meanwhile, the US ambassador to the Philippines, Sung Kim, plans another round of meetings on Monday afternoon with North Korean officials as both sides continue to prepare for Tuesday's summit in Singapore.

Tuesday's meeting will be the first between a sitting US president and a leader of North Korea, whose nuclear and ballistic missile ambitions have raised global concerns and seen tensions soar.

It is an extraordinary turnaround from the rhetoric of last year, when Trump threatened the North with "fire and fury" and Kim dubbed him a "mentally deranged US dotard."

The summit has raised hopes of progress towards a peace treaty to formally end the Korean War, the last festering legacy of the Cold War, after hostilities only stopped with an armistice.

But Pyongyang is demanding as yet unspecified security guarantees and the end of what it calls a "hostile policy" towards it, and has not made clear what concessions it is offering over the nuclear arsenal it calls its "treasured sword" to defend against a US invasion.

Pompeo says US objective for summit unchanged

According to US Secretary of State Mike Pompeo who briefed reporters in Singapore, there is "enormous potential" for the summit, but lowered expectations that the denuclearisation of the Korean peninsula will happen after one meeting. 

"We are hopeful the summit will have set the conditions for future productive talks," he said. 

Pompeo said Trump was "fully prepared" for the talks, and was optimistic that the outcome would be "successful", while warning that there was still "lots of work left to do."

He added that the "ultimate objective" of a historic summit with North Korea had not changed and the United States was "eager to see" if North Korea was sincere about denuclearisation.

He further added that the United States remained "committed to the complete, verifiable, irreversible denuclearisation of the Korean peninsula."

Pompeo also said Tuesday's meeting presents a test of Kim's willingness to agree to deal his nuclear weapons away for "protections" from the United States.

Possibility of a future summit 

South Korean President Moon Jae-in has no current plans to join President Donald Trump and North Korean leader Kim Jong Un at the end of their summit Tuesday in Singapore.

Moon has expressed hope that the summit will lead to a three-way declaration also including Seoul to formally end the 1950-53 Korean War. But Moon's spokesman says it's unlikely that such a declaration would take place while Trump and Kim were still in Singapore.

Trump has raised the possibility of further summits and an agreement ending the Korean War by replacing the armistice signed in 1953 with a peace treaty. China and South Korea would have to sign off on any legal treaty.