Labour leader Jeremy Corbyn released a statement condemning Prime Minister Theresa May for failing to stand up for British values. He said: "President Trump's executive order against refugees and Muslims should shock and appal us all.
"Theresa May should have stood up for Britain and our values by condemning his actions. It should sadden our country that she chose not to. After Trump's hideous actions and May's weak failure to condemn them, it's more important than ever for us to say to refugees seeking a place of safety, that they will always be welcome in Britain."
The prime minister has been criticised for refusing to speak out more strongly against the US president's policies.
Trump's administration has called a stop for all refugee admissions and has temporarily barred people from seven Muslim countries – from Iran, Iraq, Libya, Somalia, Sudan, Syria and Yemen – from entering the US for at least the next 90 days.
Theresa May has said that has said she does "not agree" with Donald Trump's refugee ban and will appeal to the US if it affects British citizens, according to Downing Street.
Trump's executive order halted the entire US refugee programme which a senior White House official said is the first step in a much broader ban, according to CNN.
British citizens travelling to the US on UK passports will be barred from entering if they have dual-citizenship with countries listed in Trump's ban on refugees.
Theresa May was asked to clarify her position, leading to Downing Street releasing a statement. "Immigration policy in the United States is a matter for the government of the United States, just the same as immigration policy for this country should be set by our government," said a spokesman. "But we do not agree with this kind of approach and it is not one we will be taking."
First Minister of Scotland Nicola Sturgeon tweeted: "The PM should have said this the first time she was asked, not hours later and only under pressure."
Conservative MP for Totnes, Sarah Wollaston, tweeted that Trump was "a sickening piece of work" and should not be invited to address the Houses of Parliament on his state visit later this year.
The ban affects one of May's own MPs. Conservative MP Nadhim Zahawi, was born in Iraq but left as a child when Saddam Hussein was in power. He has been advised by his legal team that he will be affected by the ban.
The White House official said more countries may be added to the list and that Trump's administration will adopt a "very aggressive" policy. The reasons for countries being added to the ban were unclear, with the official saying the "mandate is to keep America safe."