And until denuclearisation takes place, sanctions against North Korea would remain in place, he stressed.
Managing expectations is one of the oldest games in politics.
Security is tight ahead of the summit between two unpredictable men who in the past have threatened to destroy the other's country during the stand-off over North Korea's nukes.
"Welcomed Chairman Kim Jong-Un, who has just arrived in Singapore", Balakrishnan tweeted.
Trump has faced intense pressure to win something similar to this. "But I think that will take a little bit of time". But on the eve of the summit, he altered his schedule, opting to return at about 8 p.m. on Tuesday after a full day of meetings with Kim - nearly 15 hours earlier than previously anticipated.
Probably. In fact, Trump has been doing quite a bit of this lately. Though in sober moments he has framed the summit in Singapore this week as a mere introduction to the North Korean leader, the president, ever self-confident, has been unable to mask his apparent belief that his own unique talent as a negotiator could produce a landmark deal - on the spot.
North Korea has so far presented Kim's sudden diplomatic overtures to his neighbors and to the United States as a logical next step following what Kim has claimed is the completion of his plan to develop a credible nuclear deterrent to what Pyongyang has long claimed is a policy of hostility and "nuclear blackmail" by Washington. "The 'plus" refers to discussions on ending the Korean War".
While Trump was optimistic about prospects for the summit between the old foes, USA secretary of state Mike Pompeo injected a note of caution ahead of the first-ever meeting of sitting U.S. and North Korean leaders, saying it remained to be seen whether Kim was honest about his willingness to denuclearise.
"I'm very optimistic we will have a successful outcome with the two leaders", he said.
'Challenging Path' "We could be on a course for a more collaborative approach and lower tensions, albeit in a very challenging path forward on the North Korean nuclear issues". "They see denuclearisation as a collective suicide (and they are probably right)".
Following their initial greeting, Trump and Kim will meet face-to-face without any staffers, then for an expanded meeting and a working lunch, the statement said.
But a failure Tuesday doesn't necessarily mean a return to the animosity of 2017.
It was a far cry from previous year when Trump threatened North Korea with "fire and fury" and mocked Kim as "little rocket man", and Kim denounced the USA president as the "mentally deranged United States dotard".