Donald Trump plans to impose 25% tariffs on imports from Canada and Mexico and 10% tariffs on goods from China.
The expected move raises fears of price increases for US consumers as the American president suggested he would try to blunt the impact on oil imports.
He has been threatening the tariffs to ensure greater co-operation from the countries on stopping illegal immigration and the smuggling of chemicals used for fentanyl.
And he has also pledged to use tariffs to boost domestic manufacturing.
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"Starting tomorrow, those tariffs will be in place," White House press secretary Karoline Leavitt told reporters on Friday.
"These are promises made and promises kept by the president."
The tariffs carry both political and economic risks for Mr Trump.
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Many voters backed the Republican on the promise that he could cut inflation, but tariffs could trigger higher prices and potentially disrupt the energy, car, lumber and agricultural sectors.
Mr Trump had said he was weighing issuing an exemption for Canadian and Mexican oil imports.
"I'm probably going to reduce the tariff a little bit on that," Mr Trump said.
"We think we're going to bring it down to 10%."
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The United States imported almost 4.6 million barrels of oil daily from Canada in October and 563,000 barrels from Mexico, according to the Energy Information Administration.
US daily production during that month averaged nearly 13.5 million barrels a day.
China responded aggressively to tariffs Mr Trump imposed on Chinese goods during his first term, targeting the president's supporters in rural America with retaliatory taxes on US farm exports.
Both Canada and Mexico have said they have prepared the option of retaliatory tariffs to be used if necessary.
Canadian Prime Minister Justin Trudeau said on Friday: "We're ready with a response, a purposeful, forceful but reasonable, immediate response.
"It's not what we want, but if he moves forward, we will also act."
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Mr Trudeau said tariffs would have "disastrous consequences" for the US, putting American jobs at risk and causing prices to rise.
Mexican President Claudia Sheinbaum said on Friday that Mexico has maintained a dialogue with Mr Trump's team since before he returned to the White House.
But she emphasised that Mexico has a "plan A, plan B, plan C for what the United States government decides".
"Now it is very important that the Mexican people know that we are always going to defend the dignity of our people, we are always going to defend the respect of our sovereignty and a dialogue between equals, as we have always said, without subordination," she added.
Liu Pengyu, spokesman for the Chinese embassy in Washington, said the two countries should resolve their differences through dialogue and consultation.
"There is no winner in a trade war or tariff war, which serves the interests of neither side nor the world," Mr Liu said in a statement.
"Despite the differences, our two countries share huge common interests and space for co-operation."
Mr Trump also spoke about a plan for tariffs on the European Union without giving specific details.
He told reporters at the White House that he would "absolutely" put tariffs on the bloc, adding "the European Union has treated us so terribly".
(c) Sky News 2025: Donald Trump plans to hit Canada, Mexico and China with tariffs - amid fears US consumers