In the space of a week, U.S. President Donald Trump's tariffs on steel and aluminum went from a "no exemptions" plan to one filled with carve-outs for Canada, Mexico and likely other allies, plus hundreds of products not available domestically.

People familiar with the shift say Trump's mind was changed by a furious last-ditch lobbying campaign from the Canadian government, Republican lawmakers, business groups and even the United Steelworkers — the very union whose members stand to benefit most from the tariffs.

Trump said on Friday he was ready to work out an exception for Australia. Japan, South Korea, the European Union and Brazil called for similar treatment.