Canada is broadening its pushback against the latest U.S. decision to keep imposing duties on Canadian softwood lumber. Trade Minister Mary Ng says Canada is launching challenges under the North American free-trade deal as well as before the U.S. Court of International Trade. Nine days ago, Ottawa sought a judicial review of last month’s Treasury Department assessment of the levies. …Such a deal would be challenging since the U.S. takes issue with a long-standing regulatory system in Canada that it says puts American producers at a disadvantage. The U.S. ambassador to Canada echoed that sentiment in a statement issued Thursday evening. “The United States is open to resolving our differences with Canada over softwood lumber to ensure a level playing field for U.S. industry,” David Cohen said. …Ottawa is also challenging the Treasury Department’s fourth review under Chapter 10 of the Canada-United States-Mexico Agreement.