Prime Minister Justin Trudeau of Canada is the first G7 leader to visit President-elect Donald J. Trump in Florida since the election. He is under pressure to persuade Mr. Trump to back down from his tariff threat.

The sudden visit to Florida by the leader of Canada comes days after Trump threatened to impose a 25 percent tariff on Canadian and Mexican goods.

Canadian Prime Minister Justin Trudeau says he had an “excellent conversation” with Donald Trump in Florida after the president-elect’s threat to impose significant tariffs on two of America’s leading