A United States food importer has filed a new lawsuit challenging President Donald Trump's 50 percent tariffs on Canadian goods. The case targets a trade measure imposed after bilateral negotiations broke down in August. The breakdown followed comments by Canada's prime minister that the proposed deal would have given Washington control over who Canada could trade with. That statement exposed a dispute over the degree of influence the United States would retain over Canadian trade decisions. The importer's action turns the tariff policy into a legal contest before a United States court. The available account does not specify the importer's exact legal arguments or the remedy it is seeking. The case nevertheless adds a judicial test to a policy already tied to a failed agreement.