Amber Rudd was facing mounting pressure over her role in creating policies that denied healthcare, work pensions and benefits to long-term Caribbean residents.

Britain's Home Secretary Amber Rudd answers an urgent question on the treatment of members of the Windrush generation and their families in the House of Commons, in London, April 26, 2018.
Britain's Home Secretary Amber Rudd answers an urgent question on the treatment of members of the Windrush generation and their families in the House of Commons, in London, April 26, 2018. (Reuters)

Britain's interior minister resigned on Sunday after Prime Minister Theresa May's government faced an outpouring of indignation over its treatment of some long-term Caribbean residents who were wrongly labelled illegal immigrants.

The resignation of one of May’s closest allies is a blow as she navigates the final year of negotiations ahead of Britain's exit from the European Union in March 2019. 

It also deprives the cabinet of one of its most outspoken pro-European members.

In a resignation letter to May, Amber Rudd said she had inadvertently misled a parliamentary committee last Wednesday by denying the government had targets for the deportation of illegal migrants. 

May accepted her resignation.

For two weeks, British ministers have been struggling to explain why some descendants of the so-called "Windrush generation", invited to Britain to plug labour shortfalls between 1948 and 1971, had been denied basic rights.

The Windrush scandal overshadowed the Commonwealth summit in London and has raised questions about May's six-year stint as interior minister before she became prime minister in the wake of the 2016 Brexit referendum.

"The Windrush scandal has rightly shone a light on an important issue for our country," Rudd said in a resignation letter to May.

Rudd, who was appointed Home Secretary in 2016, said voters wanted those who had the right to reside in Britain to be treated fairly and humanely but also that illegal immigrants be removed.

Facing questions over the Windrush scandal, Rudd, 54, told lawmakers on Wednesday that Britain did not have targets for the removal of immigrants, but was forced to clarify her words after leaked documents showed some targets did exist.

The Guardian newspaper on Sunday reported a letter from Rudd to May last year in which she stated an "ambitious but deliverable" aim for an increase in the enforced deportation of immigrants.

Source: Reuters