The Trump administration headed back to the Supreme Court on Monday to block an appeals court ruling that placed limits on its ban on refugees.
The Justice Department asked the highest court to halt implementation of the ruling last week that refugees who have formal assurances of resettlement in the United States from US aid agencies are not covered by the ban.
The San Francisco Appeals Court's decision could pave the way for the entry of some 24,000 already-approved refugees beginning September 12.
The Justice Department asked the Supreme Court to place that decision on hold until the high court can review broader issues of Trump's travel ban next month.
"The Ninth Circuit's refugee-assurance ruling would upend the status quo and do far greater harm to the national interest," the Justice Department said in a filing.
It was the department's latest effort to defend President Donald Trump's repeatedly stymied order to halt the influx of refugees and limit travellers from six mainly Muslim countries.
The arguments hinged on a stipulation in the travel ban that refugees in the pipeline can only be accepted if they have a "bona fide relationship" with a US individual or entity.
The government said formal assurances from a refugee agency that may not have had direct, personal contacts with the refugee were not covered in that exception.
But opponents to the ban sued, arguing that people with formal assurances should be admitted.
In its filing Monday, however, the Justice Department opted not to fight the appeals court's ruling that bona fide relationships -- the standard for refugees and travellers from the six countries exempted from the Trump travel ban -- include grandparents, aunts, uncles, and cousins of American citizens.
Previously the ban would only have left open the door for refugee parents, spouses, children, sons- and daughters-in-law, siblings and step- and half-siblings of people in the United States.
The six countries covered in the travel ban are Iran, Libya, Syria, Somalia, Sudan and Yemen.