The US Supreme Court handed President Donald Trump a major victory on Friday by curbing the power of individual federal judges to block executive actions.
Mr Trump, in an impromptu media briefing at the White House, called the decision "a giant win".
"This morning, the Supreme Court has delivered a monumental victory for the Constitution, the separation of powers, and the rule of law in striking down the excessive use of nationwide injunctions interfering with the normal functioning of the executive branch," he said.
The case stems from Mr Trump's order denying birthright citizenship to US-born children of parents who are in the country illegally.
"Thanks to this decision, we can now promptly file to proceed with numerous policies that have been wrongly enjoyed on a nationwide basis, and some of the cases, we're talking about ending birthright citizenship, which now comes to the fore," he said.
The court's 6-3 ruling, however, did not let Mr Trump's policy come into effect immediately and did not address the policy's legality.
The court said nationwide injunctions issued by lower court judges "likely exceed the equitable authority that Congress has granted to federal courts".
The outcome was a victory for the Republican President, who has complained about individual judges putting up obstacles to his agenda.
But the ruling left open the possibility that the birthright citizenship changes could remain blocked nationwide.
Birthright citizenship automatically makes anyone born in the US an American citizen, including children born to parents in the country illegally. The right was enshrined soon after the Civil War in the Constitution’s 14th Amendment.
Mr Trump said that ruling was meant for "the babies of slaves", rather than for people "trying to scam the system".
The US is among about 30 countries where birthright citizenship — the principle of jus soli or “right of the soil” — is applied. Most are in the Americas, and Canada and Mexico are among them.
