Donald Trump joked about the “merger of Canada and the United States” whilst hosting Mark Carney in the Oval Office.

The US president promised to treat Canada fairly on tariffs during a good-natured meeting with the country’s prime minister.

“I think they’re going to walk away very happy,” Mr Trump said.

“We’re going to treat people fairly. We’re going to especially treat Canada fairly.”

In March, Mr Carney took over as prime minister from Justin Trudeau, who had famously bad relations with Mr Trump.

Mr Carney and Mr Trump have since trumpeted their convivial relations.