Several states are making fresh legal challenges
The US Justice Department has filed a brief with a federal appeals court in support of President Donald Trump's travel ban.
The Associated Press says the document was filed Monday with the 9th US Circuit Court of Appeals in San Francisco.
Earlier, lawyers for Minnesota and Washington State made the case for upholding Judge James Robart's decision to suspend the so-called Muslim Ban.
The appeal court is expected to make a speedy decision on the issue.
However, 15 other US states are making fresh legal challenges to prevent the ban being restored.
President Trump has asserted he has popular support for his ban and earlier claimed polls which suggest otherwise "are fake news".
The president is fighting to restore the controversial executive order, which was halted after a ruling by Judge Robart.
On Sunday, an appeal court denied a formal request by the US Department of Justice to lift the suspension on the ban, which temporarily blocked all refugees and citizens of seven Muslim-majority countries from entering the US.
Hitting out a CNN poll which suggested 53% of Americans were opposed to the measure, Mr Trump tweeted: "Any negative polls are fake news, just like the CNN, ABC, NBC polls in the election.
"Sorry, people want border security and extreme vetting.
He added: "I call my own shots, largely based on an accumulation of data, and everyone knows it. Some FAKE NEWS media, in order to marginalize, lies!"
Any negative polls are fake news, just like the CNN, ABC, NBC polls in the election. Sorry, people want border security and extreme vetting.— Donald J. Trump (@realDonaldTrump) February 6, 2017
I call my own shots, largely based on an accumulation of data, and everyone knows it. Some FAKE NEWS media, in order to marginalize, lies!— Donald J. Trump (@realDonaldTrump) February 6, 2017
Mr Trump's comments came as a group of prominent Democrats, including former secretaries of state John Kerry and Madeleine Albright, called for a federal appeals court to uphold its suspension of the travel ban.
It follows another brief jointly submitted to the court by 97 companies, mostly from the US tech industry.
The firms - which include Apple, Facebook, Google, Microsoft and Twitter - said Mr Trump's executive order "inflicts significant harm on American business, innovation, and growth".
They added the measure "departs dramatically from the principles that have governed our immigration law for decades".