California Governor Gavin Newsom said his state is suing to halt Donald Trump’s tariffs, setting up a high-stakes legal challenge to the president’s landmark effort to overhaul global trade. The state will file a complaint Wednesday in San Francisco federal court challenging Trump’s use of emergency powers to enact broad tariffs against Mexico,

Gov. Gavin Newsom on Wednesday is expected to announce a lawsuit arguing that President Trump lacks the authority to enact the international tariffs without the support of Congress.

Gov. Newsom says California will challenge President Trump’s authorities to impose tariffs under the International Emergency Economic Powers Act.