The World Trade Organization has advised that Canada requested dispute consultations with the United States regarding the tariffs imposed on March 4, 2025. Canada claims the additional duties on all goods are inconsistent with the General Agreement on Tariffs and Trade (GATT) 1994 and the WTO's Trade Facilitation Agreement.
More information can be found here on the WTO site: https://www.wto.org/english/news_e/news25_e/dsrfc_05mar25_e.htm