California has filed a federal lawsuit aiming to block former President Donald Trump’s sweeping new tariffs, arguing the measures exceed presidential authority and pose serious economic risks to the state and the nation.

Read also: U.S. Tariff Freeze Offers Brief Relief—Except for China, Where Rates Spike to 125%

The legal challenge, filed in San Francisco by Governor Gavin Newsom and Attorney General Rob Bonta, claims that Trump’s tariff orders—10% across-the-board and up to 145% on goods from specific nations like China—violate the U.S. Constitution by sidestepping Congress’s exclusive power over trade.

“These tariffs were imposed without warning, process, or legal justification,” the lawsuit argues, stating that the International Emergency Economic Powers Act (IEEPA), which Trump invoked, does not grant the president the authority to unilaterally impose widespread taxes on imports.

The lawsuit points to immediate and damaging fallout: volatile financial markets, diminished investor confidence, and the threat of a nationwide recession. California, the largest importer among U.S. states and the fifth-largest economy globally, is positioned to take a disproportionate hit.

The state warned that its 12 ports—which handle 40% of U.S. imports—could suffer steep revenue losses, while retaliatory tariffs from countries like China could devastate its $23.6 billion agricultural export sector, costing thousands of jobs.

“California is on the frontlines of this trade war,” the lawsuit states, calling the tariffs a direct threat to economic stability and state sovereignty.

China has responded with tariffs of its own, including a 125% levy on U.S. goods, and the European Union has signaled retaliatory measures, though enforcement is currently paused.

In response, White House spokesperson Kush Desai criticized California’s leaders, suggesting they focus on internal state issues instead. “The Trump administration is fully committed to reviving U.S. industries through every means available, including tariffs,” Desai said.

Trump has defended the measures by framing the U.S. trade deficit as a national emergency that threatens domestic manufacturing and economic independence. His executive orders rely on provisions of the IEEPA that allow special action during unusual or extraordinary threats to the country.

California’s lawsuit joins a growing legal front against the tariffs. Other suits have been filed by a small business owner in Florida, a Native American tribe in Montana, and business advocacy group Liberty Justice Center in New York, each challenging the legality and scope of the tariffs from different angles.