Trump asks unexpected question about King Charles ahead of royal visit

US President Donald Trump questioned a royal author over whether Canadians continue to "recognise the King" as their head of state, referring to the British monarch Charles III who's due to visit the US this month.

In an interview with royal biographer Robert Hardman for his forthcoming book on Elizabeth II, the US President acknowledged that Canada's two centuries of nationhood made annexation unrealistic within his remaining term.

When Hardman urged the president to "please leave Canada alone", noting it would "undoubtedly make the King of Canada unhappy", President Trump paused before questioning whether Canadians still acknowledged the monarch as their head of state.

According to Mr Hardman, whose interview with the US President was published in the Mail, Trump asked: “Do they still recognise the King? Or have they stopped that?”

When the royal author confirmed that Canadians recognise the King as their head of state, the US President quipped: "But they have these terrible politicians. They're nice to my face and then they say bad things behind my back."

The President described King Charles as a "fantastic guy", expressing particular admiration for how the monarch has handled his cancer diagnosis.

"He's a great guy and he's grown so much in the last 10 years and especially over the last couple of years as King. His fight has shown that," President Trump remarked.

Later this month, King Charles and his wife ​Queen Camilla will visit the US ⁠in a long-planned trip to mark ​the 250th anniversary of that country's ​independence from British rule, before the couple pay a visit to Bermuda.

Charles will also address ​the US Congress on April ‌28 during his visit to Washington.