Video report by ITV News Washington Correspondent Robert Moore

Donald Trump has blamed a judge for "putting our country in such peril" after he was denied an appeal for the immediate reinstatement of a travel ban on nationals from seven mainly Muslim countries.

The president had appealed against the ruling, which allows legal immigrants and refugees from Iran, Syria, Iraq, Yemen, Sudan, Somalia and Libya to enter the United States.

A verdict on Sunday read: "Appellants' request for an immediate administrative stay pending full consideration of the emergency motion for a stay pending appeal is denied."

The US Justice Department has been given until Monday to submit a reply in support of the emergency appeal.

The president slammed the decision and in a series of posts on Twitter, he wrote: "Just cannot believe a judge would put our country in such peril. If something happens blame him and court system."

He also instructed Homeland Security to check "people coming into our country very carefully", and said "the courts are making our jobs very difficult."

The president had appealed against a court ruling blocking his travel ban, saying aliens have "no constitutional rights" to enter the US.

He acted after a judge in Washington state temporarily blocked his refugee and immigration ban in an major setback for the White House.

It was forced to suspend enforcement of the ban, and Mr Trump launched a series of vitriolic attacks on US District Judge James Robart.

On Saturday, when asked about the appeal, Mr Trump told reporters: "We'll win. For the safety of the country, we'll win."

He also tweeted: "The opinion of this so-called judge... is ridiculous and will be overturned."

He later blasted the "terrible decision", saying: "The judge opens up our country to potential terrorists and others that do not have our best interests at heart."

The US Justice Department's formal appeal against the judge's order at the 9th US Circuit Court of Appeals in San Francisco, cites the "sovereign prerogative" of a president to admit or exclude aliens.

It said it is a basic principle that "an alien seeking initial admission to the United States requests a privilege and has no constitutional rights regarding his application".

On Friday a judge in Seattle placed a nationwide restraining order on the ban. Credit: AP/Marcio Jose Sanchez

Meanwhile, Mr Trump has also questioned his own lawyers.

He wondered why they were not looking at a decision, also made on Friday by a federal judge in Boston, who ruled against extending a temporary restraining order on the ban in Massachusetts that was set to expire on February 5.

The ban has caused mass confusion for many foreigners trying to reach the United States, prompting protests across the US and leading to multiple court challenges.

Critics claimed the ban was "illegal and unconstitutional" but the White House has insisted it was "lawful and appropriate."

Up to 100,000 visas were reportedly revoked when the immigration measure was introduced but now people have been hastily rearranging flights following the Seattle judge's ruling.

Airlines have been told to operate just as they were before the executive order after US Customs and Border Protection told them that individuals from the seven countries, who have visas, can now board US-bound flights.