The US Department of Homeland Security has confirmed people from seven majority-Muslim countries banned from entering the US by Donald Trump's administration will be allowed to enter once again.

A ruling by a federal judge on 4 February overturned Trump's travel ban, which suspended visas for people from Iran, Iraq, Sudan, Yemen, Somalia, Syria and Libya, in a controversial move the administration said was to allow 'extreme vetting' of travellers.

Homeland Security confirmed it had suspended the visa ban and said it was now going back to inspecting travellers' visas as it did prior to the implementation of the travel ban, complying with the court order, CNN reported.

Flights from several of the countries on the 'banned' list to the US have resumed, but it is not clear how long the ruling will last – as President Trump has vowed to fight the judge's order.

Trump has ridiculed the ruling by US District Judge James L. Robart in a series of tweets, stating: "When a country is no longer able to say who can, and who cannot, come in & out, especially for reasons of safety & security – big trouble!

"Interesting that certain Middle-Eastern countries agree with the ban. They know if certain people are allowed in it's death & destruction!

"The opinion of this so-called judge, which essentially takes law-enforcement away from our country, is ridiculous and will be overturned!"

The injunction is temporary, but it is expected that the reversal will be difficult.

The ruling means that US officials must grant visas for people travelling to the US from the seven countries identified in the ban: Iraq, Syria, Iran, Libya, Somalia, Sudan and Yemen.