Donald Trump is the “biggest threat to Canada since World War Two”, a leading candidate to replace Justin Trudeau as prime minister warned on Monday.

Chrystia Freeland, who served as Mr Trudeau’s deputy prime minister before resigning in December 2024, made the claim during a televised French-language debate between the candidates that are vying to be the next leader of the ruling Liberal Party.

The debate was dominated by Mr Trump and his threats to annex or slap punishing tariffs on Canada, with contenders attempting to present themselves as the best choice to take on the new US president.

Ms Freeland, who helped negotiate the US-Canada-Mexico trade deal during the first Trump administration, said the US president had at that time vowed to wage economic war against Canada.

Referring to Mr Trump urging Canada to become part of America, she said: “But this time Trump’s threats are worse – he wants to make Canada the 51st state.

“That is why he is supporting Vladimir Putin’s criminal attempt to redraw Ukraine’s borders. Trump wants to redraw our borders too.”

The former deputy prime minister added: “Trump represents the biggest threat to Canada since World War Two.” 

Mark Carney, the former Bank of England governor who polls indicate is the front-runner, said Mr Trump would never succeed in making good his threat to make Canada a part of the United States.

He said: “At this moment Canada is facing the worst crisis of our lives... I know how to handle crises.”

Mr Carney, 59, headed the Bank of England during the Brexit vote and the Bank of Canada during the 2008-2009 financial meltdown.