The U.S. Trade Representative's office said in a statement that it will work with Canada to resolve U.S. concerns over the new tax enacted in June, through the consultations. But if an agreement cannot be reached after 75 days, it may request a dispute settlement panel under the U.S.-Mexico-Canada Agreement on trade (USMCA).

The request for consultations is the first step in the USMCA's dispute resolution process, which ultimately could lead to the imposition of retaliatory U.S. tariffs on imports from Canada.

In Ottawa, a Canadian government official said the U.S. move was not concerning or a surprise. The official, who requested anonymity given the sensitivity of the topic, said the challenge was part of a conversation between the two nations.

The U.S. government has repeatedly objected to the planned Canadian tax. The offices of Canadian Finance Minister Chrystia Freeland and Trade Minister Mary Ng were not immediately available for comment.

USTR had previously readied retaliatory duties against seven other countries that had imposed digital services taxes (DSTs) - Austria, Britain, France, India, Italy, Spain and Turkey - but these have been suspended as global negotiations continue over the reallocation of taxing rights on large, multinational companies. This shift was meant to replace DSTs, but those talks have stalled over technical details.

USTR has found unilateral digital services taxes, largely aimed at collecting revenues from U.S. technology giants such as Alphabet's Google, Apple, Amazon.com and Meta, to discriminate against U.S. companies.

"The United States opposes unilateral digital service taxes that discriminate against U.S. companies. USTR is taking action today to address Canada's discriminatory policies,” U.S. Trade Representative Katherine Tai said in a statement.

"As we pursue these consultations, we will continue to support the Department of the Treasury in the OECD/G20 global tax negotiations to bring a comprehensive solution to the challenge of DSTs," Tai said.