North Korean leader Kim Jong-un has arrived in Vietnam for a summit with US President Donald Trump, where they will try to reach an agreement on the North’s pledge to give up its nuclear weapons program.

Mr Trump is due to arrive in the Vietnamese capital, Hanoi, on Tuesday night.

Mr Trump will meet Mr Kim for a brief one-on-one conversation on Wednesday night, followed by a dinner, at which they will each be accompanied by two guests and interpreters, White House spokeswoman Sarah Sanders told reporters on Air Force One.

She said that would be followed by more meetings between the two leaders on Thursday.

Their talks come eight months after their historic summit in Singapore, the first between a sitting US president and a North Korean leader.

While there is no real expectation that the second meeting will bring a final deal on ridding North Korea of nuclear weapons that threaten the United States, there are some hopes it could lead to a declaration that the 1950-53 Korean War is at last formally over.

But, in return, the US would expect significant movement by Mr Kim towards denuclearisation.

In Singapore, Mr Kim pledged to work toward complete denuclearisation of the Korean peninsula, but the vague agreement struck there has produced few concrete results. US Democratic senators and security officials have warned Mr Trump against cutting a deal that would do little to curb North Korea’s nuclear ambitions.

Mr Kim travelled from the North Korean capital, Pyongyang, by train. It crossed the border from China into Vietnam at the border town of Dong Dang.

Vietnamese officials were on hand to receive him at the station with a red-carpet, including a guard of honour and North Korean and Vietnamese flags flying.

Mr Kim left his train in Dong Dang and set off on the last 170 kilometres of his journey to the Vietnamese capital, Hanoi, by car.

Both Mr Kim and Mr Trump are also due to hold separate talks with Vietnamese leaders.

US Secretary of State Mike Pompeo also arrived in Hanoi, on Tuesday, a reporter travelling with him said.

-AAP