The court's action, which came in a brief written order on Wednesday, effectively set interim rules that allow the administration to enforce its asylum restrictions while legal challenges to the policy continue, reports Efe news.
The order stayed the effect of lower court injunctions that barred the administration's plans. One of those injunctions was issued earlier this week by a federal judge in California.
The policy, one of several measures the Trump administration has taken to deter immigration from Latin America, demands that refugees seek asylum in a safe country they enter before reaching the US. T
he rules effectively cut off most asylum claims by people coming from El Salvador, Guatemala or Honduras.
The court's unsigned order, a single paragraph that didn't provide its legal rationale, allows the government to implement the policy while litigation proceeds. The justices' action isn't a ruling on the merits of the case, which is still proceeding in lower courts.
Wednesday's action stands in contrast to an earlier Supreme Court order from December 2018 where, with a 5-4 vote, the justices declined to lift lower court orders blocking a less severe Trump administration policy that denied asylum eligibility to applicants who didn't present themselves at an official port of entry.
It wasn't immediately clear how the court distinguished between the two cases.
"Big United States Supreme Court win for the border on asylum," Trump said on Twitter in reaction to the court's order.
The American Civil Liberties Union, which represents the East Bay Sanctuary Covenant and other immigrant-rights groups challenging the policy, argued in legal papers that the administration was attempting "a blatant end-run around the scheme Congress created" to manage asylum applications.
The Supreme Court's action means the Trump restrictions can be enforced along the entire border - and likely for many months. Litigation in the case could take another year or longer to conclude.
In July, US District Judge Jon Tigar in Oakland, California, issued a nationwide injunction halting implementation of the rule while litigation over its legality proceeded.
The US Court of Appeals for the Ninth Circuit, in San Francisco, later narrowed the injunction to its own circuit, which includes the southern border states of Arizona and California. That meant the administration couldn't enforce the restrictions there, but it could in New Mexico and Texas.
The Trump administration has suffered an array of legal setbacks in its bid to take a tougher stance with immigration policy, but the tide has started to shift in recent months.
The White House scored another notable victory in May with the Ninth Circuit appeals court allowed the administration to continue returning Central American migrants to Mexico while their requests for asylum in the US are adjudicated. Litigation in that case also is ongoing.
The Supreme Court in November will consider whether the Trump administration acted lawfully when it cancelled an Obama-era program, called Deferred Action for Childhood Arrivals, that provided benefits to undocumented immigrants who were brought to the US as children. The program remains in effect for now.
( With inputs from IANS )