A U.S. appeal court late on Saturday denied a request from the U.S. Department of Justice to immediately restore a immigration order from President Donald Trump barring citizens from seven mainly Muslim countries and temporarily banning refugees.

The court ruling dealt a further setback to Trump, who has denounced the judge in the state of Washington who blocked his executive order on Friday. In tweets and comments to reporters, the president has insisted he will get the ban reinstated.

Trump says the temporary immigration restrictions on citizens from Iran, Iraq, Libya, Somalia, Sudan, Syria and Yemen, and on all refugees, are necessary to protect the United States from Islamist militants. Critics say they are unjustified and discriminatory.

The judge's order and the appeal ruling have created what may be a short-lived opportunity for travellers from the seven affected countries to get into the United States while the legal uncertainty continues.

In a brief order, the appeals court said the government's request for an immediate administrative stay on the Washington judge's decision had been denied. It was awaiting further submissions from Washington and Minnesota states on Sunday, and from the government on Monday.

The government's appeal says the decision by judge James Robart in Washington poses an immediate harm to the public, thwarts enforcement of an executive order and "second-guesses the president’s national security judgement about the quantum of risk posed by the admission of certain classes of (non-citizens) and the best means of minimizing that risk".

Trump denounced the "so-called" judge in a series of tweets on Saturday and told reporters: "We'll win. For the safety of the country, we'll win."

IRAQI FAMILY

The president's Jan. 27 order has drawn criticism even from U.S. allies and created chaos for thousands of people who have, in some cases, spent years seeking asylum in the United States.

Iraqi Fuad Sharef, together with his wife and three children, spent two years obtaining U.S. visas, and had packed up to move to America last week, but were turned back to Iraq after a failed attempt to board a U.S.-bound flight from Cairo.

On Sunday, the family checked in for a Turkish Airlines flight to New York from Istanbul.

"Yeah, we are very excited. We are very happy," Sharef told Reuters TV. "Finally, we have been cleared. We are allowed to enter the United States."

Rana Shamasha, 32, an Iraqi refugee in Lebanon, was due to travel to the United States with her two sisters and mother on Feb. 1 to join relatives in Detroit until their trip was cancelled as a result of the travel ban.

She is now waiting to hear from U.N. officials overseeing their case. "If they tell me there is a plane tomorrow morning, I will go. If they tell me there is one in an hour, I will go," she told Reuters by telephone in Beirut, saying their bags were still packed. "I no longer have a house here, work, or anything," she said.

An official at Beirut airport said three Syrian families had left for the United States via Europe on Sunday morning.

LEGAL ARGUMENTS

In his ruling in Washington state on Friday, Judge Robart questioned the use of the Sept. 11, 2001, attacks on the United States as a justification for the ban, saying no attacks had been carried out on U.S. soil by individuals from the seven affected countries since then.

For Trump's order to be constitutional, Robart said, it had to be "based in fact, as opposed to fiction".

The 9/11 attacks were carried out by hijackers from Saudi Arabia, the United Arab Emirates, Egypt and Lebanon, whose nationals were not affected by the order.

The Justice Department appeal criticized Robart's legal reasoning, saying it violated the separation of powers and stepped on the president's authority as commander-in-chief.

The appeal said the state of Washington lacked standing to challenge the order and denied that the order "favours Christians at the expense of Muslims."The U.S. State Department and Department of Homeland Security said they were complying with Robart's order and many visitors are expected to start arriving on Sunday, while the government said it expects to begin admitting refugees again on Monday.