Trump unveils sweeping US tariffs on Canada, Mexico, China

President Donald Trump announced broad tariffs Saturday on major US trading partners Canada, Mexico and China, claiming a "major threat" from illegal immigration and drugs, a move that sparked promises of retaliation.

Canadian and Mexican exports to the United States will face a 25 percent tariff starting Tuesday, although energy resources from Canada will have a lower 10 percent levy.

Goods from China, which already face various rates of duties, will see an additional 10 percent tariff.

Trump's orders also suspended exemptions allowing low-value imports from the three countries to enter the US duty-free.

The announcement threatens upheaval across supply chains, from energy to automobiles to food.

Trump invoked the International Emergency Economic Powers Act in imposing the tariffs, with the White House saying "the extraordinary threat posed by illegal aliens and drugs, including deadly fentanyl, constitutes a national emergency."

"Corresponding countermeasures"

The aim is to hold all three countries "accountable to their promises of halting illegal immigration and stopping poisonous fentanyl and other drugs from flowing into our country," the White House added.

China's commerce ministry said in a statement it would take "corresponding countermeasures" and file a claim against Washington at the World Trade Organization.

Mexican President Claudia Sheinbaum announced that her country would impose retaliatory tariffs.

Sheinbaum said she had told her economy minister "to implement Plan B that we have been working on, which includes tariff and non-tariff measures in defense of Mexico's interests."

Canadian Prime Minister Justin Trudeau -- who spoke with Sheinbaum -- separately said his country would hit back with 25 percent levies of its own on select American goods worth €102 billion, with a first round on Tuesday followed by a second one in three weeks.

"We're certainly not looking to escalate. But we will stand up for Canada, for Canadians, for Canadian jobs," he said, as he warned of a fracture in longstanding Canada-US ties.

Trump has repeatedly expressed his approval of tariffs as a policy measure, and has signaled that Saturday's action could be the first volley in further trade conflicts to come.

This week, he also pledged to impose future duties on the European Union.

He has also promised tariffs on semiconductors, steel, aluminum, oil and gas.

"Tariffs are a powerful, proven source of leverage for protecting the national interest," the White House said.

(With newswires)