President Trump labels Meghan, Duchess of Sussex, ‘nasty’.

US President Donald Trump has labelled Meghan, Duchess of Sussex, 'nasty’ just one day before his scheduled visit to the UK.

US President Donald Trump has waded into the United Kingdom’s political maelstrom days before he is set to embark on his first state visit there, calling Meghan, the Duchess of Sussex, “nasty” and saying Boris Johnson would be an “excellent” prime minister.

US President Donald Trump and First Lady Melania Trump are set to visit the UK. Picture: AP

Trump referred to the American-born Duchess of Sussex as “nasty” over comments she made in 2016 threatening to move to Canada if Trump won the White House. “I didn’t know that she was nasty,” he said of Meghan when read her prior criticism.

The former Meghan Markle married Prince Harry, the Duke of Sussex, in 2018 and gave birth to their first child, Archie, in May.

Britain's Prince Harry, Duke of Sussex, and his wife Meghan, Duchess of Sussex, pose for a photo with their newborn baby son, Archie Harrison Mountbatten-Windsor. Picture: AFP

During the state visit, the president, his wife, Melania, and his four adult children are expected to meet with Harry as well as his brother, Prince William, the Duke of Cambridge, and his wife, Kate, the Duchess of Cambridge.

Meghan is likely to stay home with Archie.

Trump told the newspaper he didn’t know that he wouldn’t be meeting Markle but predicted that she will make “a very good” American princess.

US President Donald Trump has pronounced Boris Johnson would be an ‘excellent’ British Prime Minister. Picture: AFP

Trump’s first visit to the UK as president was marred by similar critical comments he made to the same tabloid last year about May’s handling of Brexit. Trump is scheduled to arrive in London on Monday for a three-day visit.

In an interview with the British tabloid The Sun, Trump also expressed support for the controversial ex-foreign secretary in his bid to replace Theresa May, saying, “I think Boris would do a very good job. I think he would be excellent.”

As for May, Trump criticised her handling of Brexit negotiations with the European Union, saying she “didn’t give the European Union anything to lose.”

May is to step down amid an impasse over Brexit on June 7, just days after Trump is set to be feted by Queen Elizabeth II at Buckingham Palace and after official observances of the 75th anniversary of D-Day are concluded.