The Canadian government has asked the World Trade Organization to authorize the punitive measures on a range of American goods.
The action hinges on whether the United States Congress amends a law at the centre of a three-country trade dispute.
Canada and Mexico are fighting U.S. meat-labelling rules that require a sticker identifying where livestock was born, raised and slaughtered.
Backers of the labelling say consumers have a right to know where their food comes from.
But industry groups, Canada and Mexico call it a thinly disguised protectionist measure that complicates the sorting process for Americans who import foreign meat.
The WTO has repeatedly sided with Canada and Mexico in the dispute and the last appeal decision set the stage for possible retaliatory tariffs.
In a race to avoid such tariffs, the U.S. Congress has begun studying a bill that would repeal the labelling rules: it's likely to gain easy passage in the House of Representatives, but could face a tougher fight in the Senate.
"The United States is out of options and out of time," Canada's Agriculture Minister Gerry Ritz said in a statement.
"The only way for the United States to avoid billions in immediate retaliation is to repeal COOL (country-of-origin labelling)."
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