Washington (dpa) - President Barack Obama's executive order shielding millions of illegal immigrants from deportation was blocked from going into effect after the US Supreme Court split on the proposal Thursday.
The court currently has eight members, after the death of Justice Antonin Scalia earlier this year, and split 4-4. The tie means a lower court ruling stands.
"The judgement is affirmed by an equally divided Court," the court wrote in a one-sentence decision.
It did not provide details about how justices had voted or the reason for the split.
Obama said the failure of the divided court to reach a decision on the case "doesn't just set the system back further, it takes us further from the country we aspire to be."
"Today's decision is frustrating to those who seek to grow our economy and bring a rationality to our immigration system and allow people to come out of the shadows," he said.
The ruling reflects the need to confirm a ninth justice, Obama said, blaming the opposition-led Senate for failing to give a hearing to Merrick Garland, his nominee to replace Scalia.
Immigration advocates expressed dismay at the impasse and called for the court to take the matter back up once the court has a full slate of justices.
"Today, the eight justices failed to act, and countless families will suffer as a consequence," said Marielena Hincapie, executive director of the National Immigration Law Centre.
The case reached the Supreme Court after a lower court struck down Obama's 2014 executive order, which prevents deportation of many undocumented residents whose children were born on US soil, and grants them work permits.
Obama said the order was necessary because Congress had failed to pass immigration reforms.
Speaker of the House Paul Ryan, the top Republican in Congress, said the court's action showed Obama had overstepped his authority.
"The Constitution is clear: The president is not permitted to write laws. Only Congress is," he said.
Obama insisted Thursday that his administration would continue with its other immigration action that shielded immigrants brought to the country as children from deportation. That programme was not under consideration by the court.
Officials would instead continue to prioritize deportations for people who have committed crimes and those who recently crossed the border or were threats to national security.
Arguments in the Supreme Court focused on whether Obama's order required the approval of Congress, whether the programmes expanded by the order are legal under federal law and whether state governments have legal grounds to challenge the executive branch's enforcement of federal law.
The lower court decisions had found that Texas, which was among 26 states suing to block the Obama policy, had a well-founded legal argument that Obama's executive order "clearly legislated a substantive rule without complying with the procedural requirements" of US law.
The Justice Department has argued that the lower court's ruling interfered with the executive branch's proper discretion and causes "far-reaching and irreparable humanitarian impact."
Donald Trump, who has made immigration a central part of his campaign for president, including calling for construction of a border wall with Mexico, praised the Supreme Court for blocking "one of the most unconstitutional actions ever taken by a president."
He said the election would determine the course of US immigration policy, deciding "whether or not we have a border and hence a country."
Obama argued that the case showed the importance of the election, saying it would help determine whether immigration reform can be passed into law.