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U.S. President Donald Trump awaits the arrival of British Prime Minister Keir Starmer at the White House on Feb. 27, in Washington.Evan Vucci/The Associated Press

U.S. President Donald Trump says he plans to impose 25-per-cent tariffs on goods from Canada and Mexico on Tuesday, alleging drugs are “still pouring into” the United States from both countries.

Mr. Trump had paused the threatened tariffs on Feb. 3 for 30 days after Canada and Mexico pledged new measures to strengthen surveillance of their shared borders with the United States as well as more efforts to fight the illegal production and distribution of the opioid fentanyl. He also said the delay would allow time to reach a “final economic deal.”

On Thursday, he said the new measures were not enough.

“We cannot allow this scourge to continue to harm the USA,” he posted on Truth Social. “And therefore, until it stops, or is seriously limited, the proposed TARIFFS scheduled to go into effect on MARCH FOURTH will, indeed, go into effect as scheduled.”

In an Oval Office meeting with British Prime Minister Keir Starmer on Thursday, the President reiterated that tariffs on Canada and Mexico will come in on Tuesday, saying both countries are not doing enough to stop the flow of fentanyl into the United States.

“The drugs continue to pour into the country, killing hundreds of thousands of people,” he told reporters.

He disagreed when a reporter pointed out that only 1 per cent of fentanyl comes from Canada.

“They are only apprehending 1 per cent. You are right about that. It’s a little more than that but they should be apprehending much more because a lot comes through Canada. As Mexico gets stronger in terms of the border, it goes up to Canada and a lot drugs are coming through Canada,” he said.

The President said he also intends to impose reciprocal tariffs on April 1 that would affect Canada and other U.S. trading countries.

“We’ll charge countries what they charge us,” he said. “If somebody charges us 25 per cent, we charge them 25 per cent.”

Mr. Trump also lauded Britain, France and Australia as trusted allies but made no mention of Canada, its closest neighbour who jointly operates North Aerospace Defence Command to protect North America from attack.

Responding to Mr. Trump, Prime Minister Justin Trudeau told media during a visit to Montreal that Canada would answer the United States with retaliatory tariffs on Tuesday if Washington proceeds with the levies.

“If ever they do go forward with these tariffs, which are completely unjustified, we will have a strong, immediate and certain answer,” he said.

The Prime Minister warned later that Americans will also suffer in a trade war with Canada, and he rejected Mr. Trump’s repeated talk of making this country the 51st state. He said Canadians need to take this annexation talk seriously since it’s coming from the U.S. President, but he added it’s “something that will never happen.”

Public Safety Minister David McGuinty, Immigration Minister Marc Miller and Ottawa’s new fentanyl czar Kevin Brosseau are in Washington for several days of meetings as Canada tries to persuade the Trump administration to relent on the March 4 tariffs. The threatened tariff on Canadian energy shipments and critical minerals would be 10 per cent.

The ministers and fentanyl czar were scheduled to meet with U.S. border czar Tom Homan on Thursday.

Speaking to reporters in Washington before his meetings, Mr. McGuinty said he thinks Canada has acted on U.S. concerns about border security and fentanyl trafficking.

“Any test that was put on this country, on Canada, in terms of showing progress and meeting standards for the border – I believe those have been met,” Mr. McGuinty said outside of the White House.

Other meetings Thursday for the Canadian delegation included Ryan Zinke, a Republican Congressman who is a co-chair of the Northern Border Caucus, a congressional group focused on immigration, crime and national security at the Canada-U.S. border, as well as Republican Senator Marsha Blackburn.

Mr. Trudeau said the United States needs to acknowledge that Canada is a relatively small source of illegal drug shipments into U.S. territory.

On Thursday, the Canada Border Services Agency announced the latest results from its Operation Blizzard crackdown on illegal contraband entering or leaving Canada. In February alone, in collaboration with law enforcement partners, it made six seizures amounting to 56.1 grams of fentanyl, including 20 fentanyl pills and 23 grams of a substance “believed to be fentanyl” it obtained from two U.S. citizens at a Windsor-Detroit border crossing.

It also said it seized 186 kilograms of methamphetamine and 42 kg of cocaine at the Coutts port of entry, as well as many other narcotics including 30.6 grams of “suspected heroin” at the Peace Bridge port of entry.

In his social-media post Thursday, Mr. Trump also reminded Canada and Mexico that additional tariffs will be applied on countries April 2. “The April Second Reciprocal Tariff date will remain in full force and effect,” he said.

Early April is when the Trump administration plans to announce what it calls “reciprocal tariffs” against other countries, including Canada. This is to combat what Washington believes are unfair duties, trade barriers or taxes imposed on the U.S. by other countries.

Additionally, the United States has announced 25-per-cent tariffs on global imports of steel and aluminum, including from Canada.

Mr. Trump’s tariff threats appear to be based on faulty data. The White House has noted 43 pounds of fentanyl had been seized at the northern border last fiscal year, representing a “massive 2,050-per-cent increase” compared with the fiscal year prior, when two pounds of fentanyl was intercepted.

As The Globe and Mail recently reported, however, about one-third of this 43-pound tally was seized in July in Spokane, Wash., – more than 150 kilometres from the border with Canada – as part of an investigation that led to charges against three Mexican nationals. That bust has no known connection to Canada.

With reports from The Canadian Press