WASHINGTON — US President Donald Trump’s administration is urging the Supreme Court to uphold his executive order restricting birthright citizenship for children born in the United States to parents who are in the country illegally or temporarily.

The Justice Department petition sets the stage for a high-stakes constitutional fight that could bring a definitive ruling by early summer, The Associated Press reported.

Trump signed the order on his first day of his second term, seeking to end more than 125 years of legal precedent under the 14th Amendment, which guarantees citizenship to nearly everyone born on U.S. soil. Lower courts have consistently blocked the order, ruling it unconstitutional or likely unconstitutional.

Solicitor General D. John Sauer wrote in the government’s filing that “the lower court’s decisions invalidated a policy of prime importance to the president and his administration in a manner that undermines our border security.”

Opponents say the order is plainly illegal. “This executive order is illegal, full stop, and no amount of maneuvering from the administration is going to change that,” said Cody Wofsy, an attorney with the American Civil Liberties Union representing children who would be affected.

“We will continue to ensure that no baby’s citizenship is ever stripped away by this cruel and senseless order.”

The administration is appealing two cases: a July ruling by the 9th U.S. Circuit Court of Appeals that upheld a nationwide injunction, and a New Hampshire federal judge’s decision in a class-action lawsuit covering all children potentially impacted.

While the Supreme Court ruled in June to limit nationwide injunctions, it did not decide whether the underlying birthright citizenship restrictions are constitutional.

Every lower court to consider the issue so far has concluded that Trump’s order violates the 14th Amendment, which was enacted to guarantee citizenship for Black people, including formerly enslaved individuals.

If the justices take up the case, arguments are likely to be scheduled for late winter or early spring, with a ruling before the end of the court’s term. — Agencies