HANOI - United States President Donald Trump and North Korean leader Kim Jong Un kicked off talks on Thursday (Feb 28) morning aimed at resolving a decades-old nuclear deadlock.

The two leaders met at the Sofitel Legend Metropole Hanoi, a colonial hotel in the heart of Vietnam's capital city Hanoi, from about 10am Singapore time and will hold a one-on-one meeting that is scheduled to last 45 minutes.

Mr Kim said: "We have made lots of effort so far. Now it's time for us to come to Hanoi, sit together and have this wonderful dialogue. Let me assure you I will do all my best to bring a good result, ultimately, today."

The North Korean leader said there are many sceptics about the summit, but added that he is "sure all of them will be watching the moment we are sitting together, side-by-side, as if they are watching a fantasy movie".

Mr Trump stressed that he is in no rush for things to happen.

"Speed is not important to me," he said, adding that he appreciated that Mr Kim had stopped testing his nuclear weapons. He also described their relationship as strong and said he looked forward to helping turn North Korea into an economic powerhouse.

After the one-on-one meeting, Mr Trump and Mr Kim took a stroll across the hotel garden, accompanied by their interpreters. They were greeted by US Secretary of State Mike Pompeo and Mr Kim Yong Chol, the North Korean leader's right-hand man.

The two leaders seemed very cordial with each other and relaxed as they headed into the expanded bilateral meeting, where negotiations are expected to take place.

The expanded bilateral meeting will be followed by a working lunch and a joint agreement signing ceremony at around 3pm.

The two leaders are widely expected to discuss concessions that can include a declaration to end the 1950-53 Korean War, the North dismantling its main nuclear facility at Yongbyon, and the US easing sanctions to allow inter-Korea economic projects to resume.

The two men first met on Wednesday night for a one-on-one chat and dinner, which lasted over two hours.

Mr Trump hinted at something big to come when he said after the 30-minute chat that "a lot of things are going to be solved" and it will lead to a "wonderful situation long term".

Mr Kim said he will "really try" to make a successful summit and produce a "great outcome" welcomed by everyone.

North Korean state media reported on Thursday that the two leaders had sincere and in-depth discussions.

"Considerable progress made in the bilateral relations after the Singapore summit were highly appreciated and sincere and deep opinions were exchanged with a view to making comprehensive and epoch-making results in the talks in order to meet the interest and expectation of the whole world for the successful Hanoi summit," the Korean Central News Agency said.

In Singapore, the two leaders inked a four-point agreement to build new ties, establish a peace regime on the Korean peninsula, work towards complete denuclearisation, and return war remains.

Little progress has been made since, due to US insistence to stick to pressure and sanctions until the North takes concrete action. Pyongyang, however, is pushing for corresponding measures by Washington.

US-based digital news site Vox, citing three sources familiar with the negotiations, reported that a tentative new deal includes the signing a peace declaration to symbolically end the Korean War and the North promising to stop producing materials for nuclear bombs in Yongbyon.

Also included are the establishment of liaison offices that would pave the way towards normalisation of diplomatic ties, and a commitment by the North to return more war remains.

In return, the US would lift some sanctions that would allow inter-Korea economic projects to resume.

Mr Kim in his New Year's Day address called for the resumption of two major stalled inter-Korea projects - the Kaesong Industrial Complex and Mount Kumgang tours.

An end-of-war declaration is also coveted by North Korea as it will end the longstanding animosity between the two foes and provide a security guarantee for the regime. The Korean War was only halted by an armistice, which was never replaced with a peace treaty.

How the final agreement will pan out depends on Thursday's talks.

Mr Shawn Ho, associate research fellow at the S. Rajaratnam School of International Studies in Singapore, said that Mr Trump will need Mr Kim to give big concessions, for the US president to claim the talks as a "victory".

"But big concessions from Kim will also require big concessions from Trump," he told The Straits Times.

"The North Koreans know that time is not on Trump's side and they will play the game accordingly. They have little to lose at this stage of the negotiations. They just have to hold tight and see what Trump will offer them."

Mr Trump is expected to hold a press conference before departing Hanoi around 7pm.

Mr Kim will stay on so he can meet Vietnamese leadership on Friday (March 1) and Saturday (March 2).