THERESA May’s immigration policies are “institutionalised racism”, Labour frontbencher Dawn Butler claims.

Butler, whose parents are Jamaican, hit out yesterday over the Windrush scandal, which has seen citizens from Commonwealth countries and their children denied NHS access and welfare support despite decades of legal residence.

On Thursday May – who introduced rule changes now affecting Windrush families while Home Secretary – apologised during Prime Minister’s Questions. A task force has been established to handle cases where people have been challenged to provide documentary proof of their right to live in the UK.

But yesterday Butler told Sky News: “Theresa May has presided over racist legislation that has discriminated against a whole generation of people from the Commonwealth.

“Her policies, that she has implemented, have disproportionately affected people from the Commonwealth and people of colour. If you look at what institutional racism is, that’s what her policies are currently delivering.

“Theresa May has to not only reconsider her position, but she has to reconsider her policies, and an apology is not good enough.”

Meanwhile, pressure remains on Amber Rudd to quit as Home Secretary.

When asked about Rudd’s handling of the matter last week, May praised her for acting “swiftly”. But yesterday SNP Westminster leader Ian Blackford MP said “the clock is ticking” for both of them, accusing the government of “intolerance and vindictiveness”.

Blackford said: “It is unbelievable that we have not seen a sacking or resignation in the Home Office.

“Amber Rudd has failed in her responsibilities – she has shown the Home Office at its most incompetent and callous – and has undoubtedly damaged the UK’s standing.”

He went on: “The Prime Minister has presided over the utter misery and anxiety for all those caught up in her department’s incompetence. It was Theresa May who advocated the ‘hostile environment’ policies and championed the Tories anti-immigrant rhetoric. It was the Prime Minister who had to be embarrassed into meeting Caribbean leaders after initially refusing their requests.

“The deliberate decision to dispose of the landing cards of Windrush generation residents was utterly unacceptable, whichever Westminster government decreed it.”