Trump confirmed in a Sunday tweet that the U.S. would lift steel and aluminum tariffs on Canada and Mexico starting Monday.Why it matters: The move will make it easier for the USMCA, NAFTA's replacement trade deal, to be approved by the three nations. The tariffs would be replaced by stronger enforcement measures, according to Bloomberg. There will not be any quotas or limits imposed on imports of the metals, it said.Trump's confirmation:Starting Monday, our great Farmers can begin doing business again with Mexico and Canada. They have both taken the tariff penalties off of your great agricultural product. Please be sure that you are treated fairly. Any complaints should immediately go to @SecretarySonny Perdue!— Donald J. Trump (@realDonaldTrump) May 20, 2019 Go deeper: Troubles ahead for Trump's NAFTA replacement