President Donald Trump signed a series of proclamations Tuesday banning imports of Canadian beer, wine, whisky, motorcycles and dairy byproducts starting Sept. 29, escalating a trade war that saw Canada's own retaliatory tariffs take effect just hours earlier the same day.

The bans, issued under Section 338 of the Tariff Act of 1930 — a Depression-era statute never invoked until Trump used it against Canada in late August — cover most alcoholic beverages including beer, wine, cider, whisky and vodka, along with non-alcoholic beer, motorcycles, molasses and whey products, according to NBC News. The prohibitions replace 50% tariffs that had applied to those goods, cutting off market access outright rather than simply raising prices.

A senior administration official told reporters the shift to outright bans, rather than tariffs, came because several Canadian provinces bar the sale of American alcohol in their provincially run liquor stores — a retaliation-for-retaliation rationale first reported by CBC News, which cited an estimate that the ban would affect "single-digit billions" of dollars in Canadian goods. Separately, the administration is adding all-terrain vehicles, animal hides, mattresses and motorboats to its 50% tariff list while removing cement, road salt and hospital paper products, effective Sept. 15.

Why now

The move came in direct response to Canada matching U.S. tariffs "dollar for dollar," as Prime Minister Mark Carney had promised — new Canadian duties on roughly $20 billion of U.S. steel, dairy, appliances, agricultural equipment, paper and electronics goods that took effect at 12:01 a.m. Tuesday. Talks between Washington and Ottawa collapsed Aug. 21, and the administration also stripped an estimated $50 billion in Canadian-origin products from federal procurement schedules, according to U.S. Trade Representative Jamieson Greer.

Canada is the largest supplier of dairy products to the U.S. by volume, accounting for roughly 14% of American dairy imports — more than 120,000 tons last year worth about $433 million — meaning American consumers and food-service buyers could feel the pinch of the ban alongside Canadian exporters.

"Canada walked away from a near-final trade deal that offered better treatment than any other trading partner," Ambassador Greer said in a statement, calling the bans "a natural consequence of Canada's continued discriminatory treatment."

Greer added that Canada is now one of only two countries — alongside China — that has retaliated against U.S. tariffs, according to his office's statement.

Carney, for his part, rejected the White House's framing and declined to restart negotiations on Washington's terms. "When the Americans stop doing memes, stop throwing shade, stop trying to be tough and start being serious about having those discussions, we can have those discussions," he said this week, referencing a stream of AI-generated memes about Canada that Trump has posted and Treasury Secretary Scott Bessent's comparison of Canada to "a little yippy dog" in a Fox News interview. Canadian Industry Minister Dominic LeBlanc said Ottawa would assess the new bans and remains "ready for good-faith discussions" whenever Washington is prepared to engage seriously.

Trade groups on both sides of the border have warned the standoff is squeezing American farmers and manufacturers who rely on Canada as an export market, even as it raises costs for U.S. importers of Canadian alcohol and dairy. The import bans take effect Sept. 29; the revised tariff list takes effect Sept. 15. Trump has separately floated 50% tariffs on Canadian-made autos and trucks starting Jan. 1, a threat that remains under review as both governments show no immediate sign of returning to the table.