Trump's law deals with the constitutional rights of anyone born in the country.
A federal judge has blocked President Donald Trump's ban citizenship rightsa right established by law granting citizenship to anyone born in the United States.
District Court Judge John Coughenour issued a temporary restraining order on Thursday in Seattle, Washington, to stop the government from doing what he called “unconstitutional”.
“I've been on the bench for over four decades, and I can't remember a case where the question that was asked was so clear,” Coughenour said. “This is an illegal law. Where were the lawyers when this decision was made?”
Mr. Trump's order has been viewed with surprise by rights groups who portray it as a serious attack on the idea of US citizens.
The law threatened to affect not only children born in the US to undocumented parents but also children of those who immigrated to the country legally.
Monday's order, one of many Trump signatures ban immigrationwas quickly challenged in court.
Five lawsuits have been filed against Trump's attack on citizenship, involving officials from 22 states and several civil rights groups, including the American Civil Liberties Union.
Thursday's temporary ban came as a result of complaints filed by four Democrat-led states: Arizona, Illinois, Oregon and Washington. They were the first of the suits to go to court.
“Under this law, babies born today are not considered US citizens,” Washington Assistant Attorney General Lane Polozola argued at the start of the trial.
For more than 100 years, the Supreme Court has upheld the principle of citizenship by birth, meaning the 14th Amendment of the US Constitution.
It says: “All persons born or born in the United States, and governed by that country, are citizens of the United States.”
The Trump administration, however, has maintained that natural-born citizenship encourages illegal immigration to the US.
He added that the 14th Amendment was not meant to apply to people of unknown parentage because they are “not under the jurisdiction” of the US.
Trump's Justice Department described Tuesday as “an important step” in the administration's efforts to address “the ongoing crisis at the southern border”.
The law directs the Social Security Administration not to issue Social Security cards or numbers to children born after February 19 if one of their parents is not a citizen or legal permanent resident.
This causes the children to be expelled from their country. Without a Social Security card, the most important document, children can also struggle to get essential government benefits.
The US is one of the 30 countries in the world that has free citizenship. The 14th Amendment was enacted after the Civil War to extend citizenship to formerly enslaved blacks.