OTTAWA, March 2 (Xinhua) -- Canadian Prime Minister Justin Trudeau Friday called U.S. President Donald Trump's plan for tariffs on steel and aluminum imports "absolutely unacceptable" and warned of serious disruption.

Trudeau said Trump's plan will have "significant and serious" economic ramifications on both sides of the Canada-U.S. border.

"The United States has a 2-billion Canadian dollars surplus on steel with us, so we regard the imposition of any new tariffs or any tariffs on steel or aluminum between our two countries as absolutely unacceptable," Trudeau told a news conference.

He stressed that it makes no sense for the U.S. to claim there's a national security imperative for imposing the duties, given the level of security cooperation between the two countries.

"The level of cooperation and integration of our militaries, our defence of North America and our working together on a broad range of security issues means that it just makes no sense to highlight that Canada and Canadian steel or aluminum might be a security threat to the United States," he said.

Trump's announcement to impose tariffs came as Canada, the United States and Mexico continue talks to renegotiate the North American Free Trade Agreement (NAFTA).

On Thursday, Trump said that he planned a 25 percent tariff on steel and a 10 percent tariff on aluminum that would go into effect next week.

Canada is the largest steel exporter to U.S. market, with steel imports from Canada accounting for 16.1 percent of the U.S. total steel imports in 2017, according to data released by the U.S. Commerce Department.