Home Secretary Amber Rudd is facing fresh questions over her claim not to have known about immigration removal targets following the leak of a memo suggesting she was informed by officials.

The Guardian said the secret internal Home Office document referred to "a target of achieving 12,800 enforced returns in 2017-18" adding "we have exceeded our target of assisted returns".

According to the paper, the six-page memorandum was prepared by Hugh Ind, the director general of the Immigration Enforcement agency, last June and copied to Ms Rudd, Brandon Lewis, the then immigration minister, as well as a number of senior officials and special advisers.

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Shadow home secretary Diane Abbott said: "Amber Rudd either failed to read this memo, and has no clear understanding of the policies in her own department, or she has misled Parliament and the British people.

"Either way, she needs to accept responsibility and resign immediately."

The latest disclosure comes after Ms Rudd had initially denied targets were used as she was questioned by a Commons committee on Wednesday investigating the Windrush scandal.

However, after it emerged that a 2015 inspection report said the practice did exist, she said that she had never agreed to their use for migrants.

According to The Guardian, the memo said progress had been made on a "path towards the 10% increased performance on enforced returns, which we promised the Home Secretary earlier this year".

The document, dated June 21 2017, was described as a "summary of performance" by the Immigration Enforcement (IE) agency.

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It said that there were 12,503 enforced returns in 2016-17, which was considered a "success given the particularly damaging impact" from the number of late claims for asylum.

The memo goes on: "IE has set a target of achieving 12,800 enforced returns in 2017-18, aided by the redistribution of resources towards this area.

"This will move us along the path towards the 10% increased performance on enforced returns, which we promised the Home Secretary earlier this year."

The memo then turns to "assisted returns" - which covers cases such as those where an individual has left the country voluntarily on a flight paid for by the British Government.

"Typically these will be our most vulnerable returnees. We have exceeded our target of assisted returns. We set an internal target of 1,250 of these returns for 2016-17 ... we delivered 1,581."

The leak comes after a former head of the UK Border Agency (UKBA) said Ms Rudd's claim to have not known about the immigration removal targets was "disingenuous".

Rob Whiteman, who was the chief executive of UKBA from 2011 to 2013, told the BBC Radio 4 Today programme that ministers would have seen internal documents which referred to them.

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"Targets are set operationally by managers but, of course, ministers would know there are targets.

"They are intelligent people and they will see performance reports, bids to Treasury for resources, the departmental plan which would cover the targets that are being set for individual services," he said.

"Fair's fair, ministers could say we don't actually set these targets, they are being set by the operations, but I think it is disingenuous, surely, to suggest that they don't know that they exist because they will have seen them in performance reports and other internal documents."

MPs are to debate a petition calling for an amnesty for the Windrush generation which was signed by more than 177,000 people.

The Commons Petition Committee announced that a debate on the call for an amnesty "for anyone who was a minor that arrived in Britain between 1948 to 1971" along with Government compensation for "loss and hurt" will be held on April 30 in Westminster Hall.