The US commerce secretary has said President Donald Trump could dial down huge tariffs on Canada and Mexico this week while maintaining pressure on China, hours after Canada's premier attacked the United States' "dumb" trade war.

"I think he's going to work something out with them," Howard Lutnick told Fox Business on Tuesday, adding the announcement would probably come on Wednesday.

"Somewhere in the middle will likely be the outcome, the president moving with the Canadians and Mexicans, but not all the way."

Lutnick said both the Mexicans and the Canadians were on the phone with him all day today, "trying to show that they'll do better."

"And the President's listening because, you know, he's very, very fair and very reasonable," he added.

Additional tariffs

His remarks came after Trump threatened Canada with additional tariffs on Tuesday in response to Ottawa’s decision to impose duties on American products.

"Please explain to Governor Trudeau, of Canada, that when he puts on a Retaliatory Tariff on the US, our Reciprocal Tariff will immediately increase by a like amount," Trump wrote on Truth Social.

Trump had announced — and then paused — blanket 25 percent tariffs on imports from major trading partners Canada and Mexico in February, accusing them of failing to stop irregular immigration and drug trafficking.

But he pushed ahead with them Tuesday, citing a lack of progress on both fronts.