Four Republican US senators have broken ranks and voted with the Democrats in an effort to block President Donald Trump's tariffs against Canada.

In a rare display of opposition to the president, Lisa Murkowski, Mitch McConnell, Rand Paul and Susan Collins helped to vote through a resolution 51 to 48 to end Trump's emergency declaration on fentanyl trafficking that he has used to justify tariffs on Canadian imports.

"As I have always warned, tariffs are bad policy, and trade wars with our partners hurt working people most," McConnell said.

But the vote was largely symbolic, as the resolution is unlikely to pass through the Republican-held House of Representatives and be signed by Trump himself.

Democrat Tim Kaine, who led the resolution, said tariffs on Canada - which include a 25% levy on steel and aluminium - were "not about fentanyl" following the vote on Wednesday.

"It's about tariffs. It's about a national sales tax on American families," the senator for Virginia said.

Mitch McConnell, who stepped down as the US Senate's longest-serving Republican leader a few months ago, has a long history of criticising Donald Trump.

Lisa Murkowski, a senator for Alaska, and Susan Collins of Maine both represent areas that border Canada. Murkowski has also opposed Trump several times in the past.

Senator Rand Paul of Kentucky, who co-sponsored the legislation, told Fox News on Wednesday that tariffs "raise prices and are a bad idea for the economy".

"We are richer because of trade with Canada, and so is Canada", he said.

Trump criticised the four senators as being "extremely difficult to deal with and unbelievably disloyal" on his Truth Social platform.
Every Democrat also voted in favour of the resolution on Wednesday night.

Democrats argue that Trump is using the tariffs to pay for proposed tax cuts that would benefit the wealthy, and will also cause a hike in bills and costs for Americans.

However at the White House on Wednesday, Trump singled out Canada as benefiting from "unfair" trading practices with the US.
A sweeping new set of tariffs unveiled by the president on Wednesday did not target Canada because it has already been hit with other measures.

But there was no confirmation of any reprieve from a new 25% tax that Trump will charge on Americans importing foreign-made cars, which could hit Canada particularly hard.

Madina Mammadova\\EDnews