Trump is due in the Vietnamese capital, Hanoi, on Tuesday evening, Feb. 26.

They will meet for a brief one-on-one conversation on Wednesday evening, 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.

The two leaders would meet again on Thursday, she said.

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

There is likely to be pressure on both sides to move beyond the vaguely worded commitment they made in Singapore to work toward complete denuclearisation of the Korean peninsula.

Read: Kim Jong Un Begins Train Journey to Hanoi for Summit with Trump

Domestic critics have warned Trump against cutting a deal that would do little to curb North Korea's nuclear ambitions, urging specific, verifiable North Korean action to abandon the nuclear weapons that threaten the United States.

In return, Kim would expect significant U.S. concessions such as relief from punishing sanctions and a declaration that the 1950-53 Korean War is at last formally over.

Kim, who traveled from the North Korean capital by train, arrived at the station in the Vietnamese town of Dong Dang after crossing over the border from China.

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

Kim's sister, Kim Yo Jong, who has emerged as an important aide, arrived with him.

About a dozen bodyguards ran alongside Kim's car as he departed for the two-hour journey to the capital, Hanoi.

Roads were closed off with Vietnamese security forces equipped with armored-personnel carriers guarding the route to the city's Melia hotel where he is staying.

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

U.S. Secretary of State Mike Pompeo also arrived in Hanoi, on Tuesday. He has been Trump's top envoy in his efforts to improve ties with the reclusive North and has made several trips to Pyongyang to negotiate an ending of its nuclear programme.

Pompeo was due to meet U.S. Special Representative for North Korea Stephen Biegun in Hanoi later.

REUTERS