Canada has implemented tariff-rate quotas for dairy products.
The Biden administration said it will seek a disputes-settling panel under the Canada-U.S.-Mexico trade Agreement.
That will take about a month to set up and many more months to come to a conclusion.
Canada and the U.S. have been in negotiations for months over the U.S. complaints and, while Americans say there has been some progress, they still have major concerns.
Their main concern is that some of the quotas have been given to Canadian dairies. The Americans want the quotas opened to more potential customers for U.S. dairy products.
A tariff-rate quota entitles the holder to import dairy products at a tariff much lower than the regular rate.
They are a prized possession because the holders can usually make a windfall profit by selling at much higher prices into the Canadian market.