US President Donald Trump has lifted import taxes on Canadian and Mexican steel and aluminium and delayed auto tariffs that would have hurt Japan and Europe.

By removing the metals tariffs on Canada and Mexico, Mr Trump has cleared a key roadblock to a North American trade pact his team negotiated last year.

As part of the arrangement, the Canadians and Mexicans have agreed to scrap retaliatory tariffs they had imposed on US goods.

Mr Trump said in a speech to the National Association of Realtors: “I’m pleased to announce that we’ve just reached an agreement with Canada and Mexico, and we’ll be selling our product into those countries without the imposition of tariffs, or major tariffs.”

In a joint statement, the US and Canada said they would work to prevent cheap imports of steel and aluminium from entering North America.

The provision appeared to target China, which has long been accused of flooding world markets with subsidised metal, driving down world prices and hurting US producers. The countries could also reimpose the tariffs if they faced a “surge” in steel or aluminium imports.

Earlier, the White House said Mr Trump is delaying for six months any decision to slap tariffs on foreign cars, a move that would have hit Japan and Europe especially hard.

Mr Trump still is hoping to use the threat of auto tariffs to pressure Japan and the European Union into making concessions in ongoing trade talks.

Donald TrumpDonald Trump is delaying auto tariffs that would affect Japan and Europe (AP Photo/Alex Brandon)

“If agreements are not reached within 180 days, the president will determine whether and what further action needs to be taken,” White House press secretary Sarah Sanders said.

The new trade deal — the US-Mexico-Canada Agreement — needs approval the legislatures in the US, Canada and Mexico. Several key US members of Congress were threatening to reject the pact unless the tariffs were removed. And Canada had suggested it would not ratify any deal with tariffs still in place.

Canadian Prime Minister Justin Trudeau credited his government for holding out to get the tariffs removed.

He said: “We stayed strong. That’s what workers asked for. These tariffs didn’t make sense around national security. They were hurting Canadian consumers, Canadian workers and American consumers and American workers.”