Britain's Prime Minister Theresa May walks out of 10 Downing Street in London, Britain, April 18, 2018. REUTERS/Toby Melville

LONDON (Reuters) - Prime Minister Theresa May said on Wednesday the “Windrush generation”, people from the Caribbean who came to Britain as children after World War Two, were British and her government would not tell them to leave the country.

The Windrush generation were invited to Britain to plug labour shortfalls between 1948 and 1971 but some of their descendants have been caught up in a tightening of immigration rules overseen by May in 2012 when she was interior minister.

“These people are British, they are part of us,” May told parliament, repeating her apology to 12 Caribbean nations she made on Tuesday. “I want to say sorry to anyone who has had confusion or anxiety felt as a result of this.”

May, a former interior minister, told parliament the government was doing all it could to help those people who had been wrongly labelled illegal immigrants.

The opposition Labour Party demanded to know whether she was in charge when migrants’ identity documents were destroyed by the Home Office (interior ministry), but on Wednesday May told parliament that it had happened in 2009 when the opposition Labour Party was in government.

“What the prime minister said was that the decision was taken in 2009 when there was a Labour government,” her spokesman told reporters, adding that it had been an operational decision by the UK Border Agency.

He also said EU citizens had nothing to fear about their rights after Brexit after the Windrush affair.

“Very strong guarantees have been given to EU citizens ..,” he added.