The US House of Representatives has voted to rescind US President Donald Trump's tariffs on Canadian goods.

In a 219-211 vote, six Republican lawmakers joined Democrats to back a resolution seeking to end the tariffs Trump imposed on Canada last year.

The vote is largely symbolic as it will still need to be approved by the US Senate and then approved by Trump, who is very unlikely to sign it into law.

Since his re-election, Donald Trump has imposed a series of tariffs on Canada and has recently threatened a 100% import tax in response to Canada's proposed trade deal with China.

As the vote was taking place on the House floor, Trump posted on Truth Social: "Any Republican, in the House or the Senate, that votes against TARIFFS will seriously suffer the consequences come Election time."

"TARIFFS have given us Economic and National Security, and no Republican should be responsible for destroying this privilege," he added.

The vote came after US House Speaker Mike Johnson, a Trump ally in Congress, unsuccessfully tried to block discussion of Trump's tariffs on the chamber floor.

With Republicans holding a thin majority in the US House, the six Republican defections, along with a near-united front from Democrats, were enough to secure the votes.

The measure had been introduced by Democrat Gregory Meeks, who said that Trump had "weaponised tariffs" against allies and destabilised the global economy.

"Not only have these tariffs done immense harm to our relationship with Canada, pushing them closer to China, but they have also driven up prices here at home," he said before the vote.

Representative Don Bacon from Nebraska was one of the six Republicans who crossed the aisle to join Democrats in approving the measure. Before the vote, he said, "tariffs have been a 'net negative' for the economy and are a significant tax that American consumers, manufacturers, and farmers are paying."

The bill now heads to the US Senate, where Republicans also hold the majority. Even if it cleared that hurdle, it is unlikely to be signed into law.

Separately, Trump's tariffs are facing legal scrutiny, with the US Supreme Court set to rule soon on a case challenging the president's authority to impose the levies.

Meeks, the top Democrat on the US House Foreign Affairs committee, said the measure on Canada is the first of several bills he plans to introduce that aim to roll back Trump's signature trade action.

"Our fight doesn't stop here," he said in a video posted online before the vote. "I have resolutions also to end Trump's tariffs on Mexico, on Brazil, and on his Liberation Day global tariffs."