By Ismail Shakil and Tim Reid

OTTAWA (Reuters) -U.S. President-elect Donald Trump said on Saturday he discussed the border, trade and energy in a “very productive” meeting with Canadian Prime Minister Justin Trudeau amid fears of a trade war.

Trudeau paid an unannounced visit to Florida on Friday evening and had dinner with Trump at his Mar-a-Lago residence, days after Republican Trump pledged to impose 25% tariffs on Canadian and Mexican imports after he is sworn in as president in January.

That pledge has raised fears of a trade war between the U.S. and two of its biggest trading partners.

Mexico President Claudia Sheinbaum warned this week that Trump’s tariff plan would have dire consequences for both countries and suggested possible retaliation.

Trump wants to use tariffs as a tool to get Mexico and Canada to help stem the flow of illegal drugs into the U.S., particularly the deadly opioid fentanyl, and also migrants crossing illegally into the U.S.

“We discussed many important topics that will require both Countries to work together to address, like the Fentanyl and Drug Crisis that has decimated so many lives as a result of Illegal Immigration, Fair Trade Deals that do not jeopardize American Workers, and the massive Trade Deficit the U.S. has with Canada,” Trump said in a post on Truth Social.

“Trudeau has made a commitment to work with us to end this terrible devastation of U.S. Families,” he added.

Trudeau, in a post on social media X on Saturday, said he looked forward to the two working together.

“Thanks for dinner last night, President Trump. I look forward to the work we can do together, again,” Trudeau said.

The prime minister’s office did not respond to a request for comment about the meeting.

A Canadian government official, speaking on the condition of anonymity, told Reuters that it was a positive, wide-ranging dinner that lasted three hours.

On Friday, Trudeau said at a news conference in Canada he was taking the possible tariffs seriously.

“Donald Trump, when he makes statements like that, he plans on carrying them out,” he said.

Many economists have warned Trump’s plan to impose tariffs on imports will increase costs for U.S. consumers.

Trump has said tariffs on trading partners will help protect U.S. manufacturers and boost domestic job growth.

In a separate post, Trump called on the so-called BRICS countries to commit to not creating a new currency or supporting another currency over the U.S. dollar.

If those countries do so they will face “100% tariffs”, Trump said.

BRICS refers to original members of the intergovernmental group of economies: Brazil, Russia, India, China and South Africa.

It also includes Iran, Egypt, Ethiopia, and the United Arab Emirates.

“We require a commitment from these Countries that they will neither create a new BRICS Currency, nor back any other Currency to replace the mighty U.S. Dollar or, they will face 100% Tariffs, and should expect to say goodbye to selling into the wonderful U.S. Economy,” Trump wrote.

(Reporting by Ismail Shakil in Ottawa and Tim Reid in West Palm Beach, Florida; Additional reporting by David LjunggrenEditing by Nick Zieminski, Rod Nickel and Deepa Babington)

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