SACRAMENTO, the United States -- About 20 states and the city of San Francisco unleashed a legal firestorm Tuesday by filing a federal lawsuit challenging President Donald Trump's controversial executive order that would deny US citizenship to children born to undocumented immigrants and temporary visa holders.

Led by the attorneys general of California, New Jersey, and Massachusetts, the lawsuit contended that Trump's directive brazenly defied the 14th Amendment's Citizenship Clause, threatening to strip tens of thousands of American-born children of their birthright each year.

"The President's executive order attempting to rescind birthright citizenship is blatantly unconstitutional and, quite frankly, un-American," declared California Attorney General Rob Bonta when announcing the lawsuit. "California condemns the President's attempts to erase history and trample on 125 years of Supreme Court precedent."

Trump signed the order hours after taking office on Monday. It directed federal agencies to halt recognition of citizenship for children born after Feb 19, 2025, to mothers who are either undocumented or legally present on temporary visas if the father is neither a US citizen nor a permanent resident.

According to the complaint, this sweeping policy would impact approximately 153,000 children nationwide every year, including about 24,500 in California alone, according to figures derived from the 2022 data provided by the National Demographics Corporation.

The lawsuit warned that these children would be rendered effectively stateless, robbed of access to social security numbers, passports, and federal benefits, and placed at risk of deportation despite entering the world on American soil.

The states also forecast enormous financial strain, as they would lose vital federal funding for programs serving these children yet remain legally compelled to provide critical services. New Jersey, for instance, estimated that it could lose millions of dollars in federal healthcare reimbursements every year while still having to care for these young individuals.

"If this unprecedented executive action is allowed to stand, both Plaintiffs and their residents will suffer immediate and irreparable harm," the complaint insisted. "Many of these children may never be able to naturalize, nor secure citizenship from any other nation."

Central to the states' argument is the Supreme Court's landmark 1898 decision in United States v. Wong Kim Ark, which established that children born on US soil to non-citizen parents are citizens by birth under the 14th Amendment. According to the lawsuit, Trump lacked the constitutional authority to override more than a century of settled legal precedent through an executive order.

The complaint, filed in the US District Court in Massachusetts, urged the court to declare Trump's order unconstitutional and block its enforcement while the case proceeds.

According to campaign materials cited in the legal filing, the White House has staunchly defended the directive, saying it is necessary to "eliminate a major incentive for illegal immigration."

The administration now faces a looming deadline to respond.