Keir Starmer told to water down 'unfair' migrant crackdown in blow to 'stop the boats' pledge

In the letter, the group demanded Ms Mahmood scrap proposals to retrospectively extend settlement waiting periods for 2.2 million migrants already residing in the UK.

It comes after the Prime Minister narrowly clung to power, facing intense scrutiny and calls to resign over his handling of the Lord Mandelson scandal.

The rebellion is being coordinated by Poole MP Neil Duncan-Jordan, who previously called for the PM to go over the affair.

Among those also putting their names to the letter are former shadow chancellor John McDonnell, Alex Sobel from the centre-left Mainstream group, and Rachael Maskell, who spearheaded Labour's rebellion against benefit cuts last year.

Former Labour leader Jeremy Corbyn, Plaid Cymru Westminster leader Liz Saville Roberts and all four Green Party MPs have also signed the document, alongside 17 MPs from other parties and 21 peers.

The letter follows a Westminster Hall debate earlier this month where more than 40 Labour MPs lined up to condemn the crackdown as "shameful," "unfair," "un-British" and a "breach of trust."

The Home Secretary plans to double the qualifying period for indefinite leave to remain (ILR) from five to ten years, with the changes applied retrospectively to migrants already living in the UK under existing rules.

These individuals arrived during what has been termed the "Boriswave" between 2021 and 2024, and would see the rules changed after they had already begun building their lives under the existing system.

"The Government must uphold its promises – we cannot simply change the rules halfway through an agreed process," the letter states.

It continued: "The Government must immediately rule out applying new immigration rules to migrant families already in the UK. Thousands of families have planned their lives around current rules."

Signatories are also calling for a consultation process on the proposals to be halted until a full impact assessment is published.

The letter warns that thousands of vacancies already exist in social care and that the proposals risk pushing the sector closer to breaking point.

Under Ms Mahmood's proposals, workers who entered on health and social care visas would face a 15-year wait.

This would affect 616,000 individuals and their dependents who arrived between 2022 and 2024 before the visa route was closed following widespread abuse.

Those claiming benefits for up to 12 months would see an additional five years added to their wait, while claimants receiving support for longer than a year would face a 10-year penalty.

To qualify, all migrants must demonstrate a clean criminal record, English language proficiency equivalent to A-level standard, at least three years of sustainable employment, and no outstanding debts to the government, including tax, visa fees or NHS surcharge payments.

If the rebellion proves successful, the Prime Minister could be forced to renege on previous promises to get Britain's parlous immigration system under control, arguing that Britain needs a “controlled and managed” system that restores public confidence.

Sir Keir has vowed to tackle small boat crossings by stepping up action against people-smuggling gangs and strengthening border enforcement, while also reforming the asylum system to speed up removals.

On legal migration, he has signalled tighter controls on work and study visas, linking immigration more closely to skills shortages and training British workers, to reduce overall numbers over time.

Despite the mounting pressure, a Government source insisted the Home Secretary remains fully committed to pushing through the reforms.

"There is absolutely no change whatsoever," the insider stressed.

"She has made the progressive case for these reforms – that we need to act if we are to retain public consent for having an asylum system at all."

"That's not how some of the party or Parliamentary Labour Party see it, but it is very much full steam ahead on our proposals, whether illegal or legal."

Another Labour source warned that rebels risked "ignoring the voters at their peril".

"Voters have been crying out for action on immigration and have felt ignored," the insider told The Telegraph.

"It is on us to make sure that we are seen to be addressing the voters' concerns, and actually dealing with them."

GB News has approached the Home Office for comment.

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