US president Donald Trump speaks in the Roosevelt Room of the White House in Washington

Donald Trump has said he is "very, very disappointed" to hear that North Korea is rebuilding a missile site that Pyongyang has said will be closed amid ongoing denuclearisation negotiations.

Earlier, the president lashed out at a number of old enemies on Twitter, including Hillary Clinton, showing his growing frustration with House Democrats and the investigations surrounding him.

In those tweets, the president accused the Democrats of “playing games” by instigating “McCarthyite” congressional investigations against him rather than getting on with the business of government, refusing to hand over files related to his son-in-law Jared Kushner’s security clearance to the House Oversight Committee and indicating he might not co-operate with the House Judiciary Committee’s abuse of power investigation into his inner circle.

As the investigations into Mr Trump have swirled, a damning new poll has emerged suggesting two-thirds of American voters believe he committed a crime before his election.

On Tuesday, Mr Trump also walked back his decision to pull all US troops out of Syria, saying he now agreed “100 per cent” with keeping a military presence there.

Trump and Kim: leaders arrive in Vietnam for talks Show all 7 1 /7 Trump and Kim: leaders arrive in Vietnam for talks Trump and Kim: leaders arrive in Vietnam for talks Donald Trump and Vietnamese President Nguyen Phu Trong make their way to a meeting at the Presidential Palace in Hanoi Reuters Trump and Kim: leaders arrive in Vietnam for talks Donald Trump waves a Vietnamese flag as Vietnam's Prime Minister Nguyen Xuan Phuc looks on AFP/Getty Trump and Kim: leaders arrive in Vietnam for talks Donald Trump waves as he leaves the Presidential Palace in Hanoi AFP/Getty Trump and Kim: leaders arrive in Vietnam for talks North Korean leader Kim Jong-un, right, is welcomed on his arrival at the Melia Hotel in Hanoi AP Trump and Kim: leaders arrive in Vietnam for talks Kim Jong-un waves as he arrives by train in the Vietnamese border town of Dong Dang AP Trump and Kim: leaders arrive in Vietnam for talks North Korean leader Kim Jong-un receiving a situation report before the summit with Trump AFP/Getty Trump and Kim: leaders arrive in Vietnam for talks The motorcade carrying U.S President Donald Trump drives past Ho Chi Minh Mausoleum AP

Meanwhile, the president’s former lawyer, Michael Cohen, will return to Capitol Hill for a fourth day of testimony.