On Wednesday, four Republican senators — McConnell, Rand Paul, Lisa Murkowski and Susan Collins — broke ranks to pass a Democratic-led resolution demanding a halt to US tariffs on Canada. The move was largely symbolic as the bill has little hope of passing the Republican-controlled House of Representatives, but underlined the growing disquiet.

While many Republicans cast the tariff plan as a way to level the international trade playing field, Democrats slammed it as misguided policy that will

President Donald Trump's tariff plan will mean higher prices for American consumers, U.S. Sen. Maria Cantwell said.