California officials sued the Trump administration Thursday, asserting the president’s order granting the state’s farmers more access to water could lead to the extinction of several fish species.

A day earlier, President Trump authorized an Interior Department order that allows Central Valley farmers to pump more water, fulfilling a 2016 campaign promise to loosen restrictions in the state, delighting farmers and prompting anger from environmentalists. The lawsuit, filed in the U.S. District Court in San Francisco, challenges the new order and argues recent biological opinions prepared by federal agencies are unlawful.

“California won’t silently spectate as the Trump administration adopts scientifically-challenged biological opinions that push species to extinction and harm our natural resources and waterways,” said California Attorney General Xavier Becerra Thursday.

Rules for the federal Central Valley Project and California State Water Project limited water supply for Central Valley farmers during the state’s yearslong drought to protect threatened species like smelt and salmon. Farmers for years lobbied for changes to the regulations, which led them to fallow fields and take other cost-cutting measures. Many relied on alternate water sources, including wells or by buying it on the private market, but often at a much higher price.

In 2018, Mr. Trump issued a directive to federal agencies to create a new operations plan to “address inefficiencies, burdens and conflicts in water delivery,” according to the U.S. Department of Interior. A new biological opinion issued by the U.S. Fish and Wildlife Service in October asserted these new and looser pumping restrictions wouldn’t threaten smelt or salmon. The order approved this week also includes habitat restoration and other efforts to protect threatened and endangered species.