U.S. President Donald Trump arrives at Noi Bai International Airport for a second summit with North Korea's leader Kim Jong Un in Hanoi, Vietnam February 26, 2019 – PHOTO: REUTERS

HANOI (REUTERS) - North Korean leader Kim Jong Un and U.S. President Donald Trump both arrived in Vietnam on Tuesday, the eve of their second summit at which they will tackle how to implement a North Korean pledge to give up its nuclear weapons.

Trump flew into the capital Hanoi on Air Force One, touching down just before 9 p.m. (14:00 GMT).

Kim arrived by train early in the day after a three-day, 3,000 km journey from his capital, Pyongyang, through China. He completed the last stretch from a border station to Hanoi by car.

The two leaders, who seemed to strike up a surprisingly warm relationship at their first summit in Singapore last June, 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.

They will meet again on Thursday, she said.

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

While the first meeting was all about breaking the ice after decades of war and bitter animosity between their countries, this time there will be pressure on both to move beyond the vaguely worded commitment they made in Singapore to work toward the complete denuclearisation of the Korean peninsula.

Trump's critics at home have warned him 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.

Vietnamese officials were on hand to greet Kim at the station in Dong Dang town after he crossed the border from China. He got a red-carpet welcome with honour guard, military band 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 briefly ran alongside Kim's car as he set off for the two-hour journey to Hanoi, smiling and waving to children lining the route from his limousine.

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

Vietnamese authorities have been tight-lipped about the summit and have yet to announce where the two will meet.

U.S. Secretary of State Mike Pompeo also arrived on Tuesday and met Vietnamese Foreign Minister Pham Binh Minh for talks.