Democratic-led states and civil rights groups filed a slew of lawsuits challenging U.S. President Donald Trump's bid to roll back birthright citizenship on Tuesday in an early bid by his opponents to block his agenda in court.

After his inauguration on Monday, Trump, a Republican, ordered U.S. agencies to refuse to recognize the citizenship of children born in the U.S. if neither their mother nor father is a U.S. citizen or legal permanent resident.

Twenty-two Democratic-led states along with the District of Columbia and the city of San Francisco filed a pair of lawsuits, in federal courts in Boston and Seattle asserting Trump had violated the U.S. Constitution.

Two similar cases were filed by the American Civil Liberties Union, immigrant organisations and an expectant mother, in the hours after Trump signed the executive order, kicking off the first major court fight of his administration.

The lawsuits take aim at a central piece of Trump's sweeping immigration crackdown. If allowed to stand, Trump's order would for the first time deny more than 150,000 children born annually in the United States the right to citizenship, said the office of Massachusetts Attorney General Andrea Joy Campbell.

"President Trump does not have the authority to take away constitutional rights," she said in a statement.

Losing out on citizenship would prevent those individuals from having access to federal programs like Medicaid health insurance and, when they become older, from working lawfully or voting, the states say.

"Today's immediate lawsuit sends a clear message to the Trump administration that we will stand up for our residents and their basic constitutional rights," New Jersey Attorney General Matthew Platkin said in a statement.

The White House did not respond to a request for comment.

More lawsuits by Democratic-led states and advocacy groups challenging other aspects of Trump's agenda are expected, with cases already on file challenging the Elon Musk-led Department of Government Efficiency and an order Trump signed weakening job protections for civil servants.

1898 U.S. SUPREME COURT PRECEDENT

Three of the four lawsuits were filed in Massachusetts and New Hampshire. Any rulings from judges in those New England states would be reviewed by the Boston-based 1st U.S. Circuit Court of Appeals, the only federal appeals court whose active judges are all Democratic appointees.

Four states filed a separate case in Washington state, which the San Francisco-based 9th U.S. Circuit Court of Appeals has jurisdiction over. That court often stymied Trump's first term agenda, though its ideological makeup has shifted to the right thanks to judicial appointments he made.

The lawsuits argue that Trump's executive order violated the right enshrined in the Citizenship Clause of the U.S. Constitution's 14th Amendment which provides that anyone born in the United States is considered a citizen.

The complaints cite the U.S. Supreme Court's 1898 ruling in United States v. Wong Kim Ark, a decision holding that children born in the United States to non-citizen parents are entitled to U.S. citizenship.

The plaintiffs challenging the order include a woman living in Massachusetts identified only as "O. Doe" who is in the country through temporary protected status and is due to give birth in March.

Temporary protected status is available to people whose home countries have experienced natural disasters, armed conflicts or other extraordinary events and currently covers more than 1 million people from 17 nations.

Several other lawsuits challenging aspects of Trump's other early executive actions are pending.

The National Treasury Employees Union, which represents federal government employees in 37 agencies and departments, late on Monday filed a lawsuit challenging an order Trump signed that makes it easier to fire thousands of federal agency employees and replace them with political loyalists.