Carney also confirmed that he had reviewed the advertisement with Ontario Premier Doug Ford, a conservative populist and outspoken Trump critic whose government paid for the campaign, before it aired.
He said he told Ford of his opposition to the ad, saying: “It was time to speak, to discuss, to negotiate with the Americans”.
“Mr Ford has made a decision, he is independent, he can do it,” he continued, “but it’s not exactly useful.”
Ford, who later paused the campaign, wrote on social media that the ad “was intended to initiate a conversation about the impact of tariffs on American workers”.
British Columbia Premier David Eby said that his province plans to launch its own US advertisement against tariffs.
Trump said on Friday that Carney had apologised and spoke of his “very good relationship” with the Canadian Prime Minister but said trade talks between the two countries would not resume.
Carney said on Saturday that Canada is ready to restart trade negotiations when the US is ready to do so.
The relationship between Washington and Ottawa has grown increasingly strained since Trump returned to office in January, with the president imposing tariffs on Canadian goods and making repeated calls to make Canada the 51st US state.
Carney, a former central banker who won an election in April, campaigned as the best-placed candidate to handle Trump and manage the bilateral relationship between the countries.
He has repeatedly told the US leader Canada “is not for sale” but has walked back some of Canada’s retaliatory tariffs, and critics have accused him of capitulation.
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