Militant union bosses are threatening to wreak more havoc for Labour by demanding the next leader scrap Shabana Mahmood’s migrant crackdown.

The Left-wing barons said the Home Secretary’s “shameful proposals must be dropped immediately”, heaping pressure on Andy Burnham if he replaces Sir Keir Starmer as Prime Minister.

Andrea Egan, the general secretary of Unison, told her union’s annual conference that Ms Mahmood’s proposals are a “direct attack on Unison members”.

Ms Egan has previously warned of a “Windrush-style scandal” and claimed the Home Office was insulting foreign social care workers for describing them as “low-waged and low-skilled”.

Ms Egan said: “I’m not sure if politicians like the Home Secretary thought we’d just look away when they decided to come for migrants. When they decided to scapegoat them, strip away their rights and deepen exploitation. Because if they did, they couldn’t have been more wrong.

“An attack on one of us is an attack on all of us. It doesn’t matter where we come from or what we look like. Workers stick together and that’s why the entire union is four-square behind our migrant members in this fight.

“Shabana Mahmood’s shameful proposals must be dropped immediately. They’re a direct attack on Unison members and a betrayal of our most basic values.”

Under Ms Mahmood’s plan, overseas nationals face a 10-year wait to apply for indefinite leave to remain, double the current five years.

Migrants who arrived in the so-called "Boris wave" face a 10 to 15-year wait to apply for indefinite leave to remain amid fears over an influx of low-skilled workers.

And migrants could be barred from claiming benefits unless they become British citizens.

Ms Mahmood said those relying on handouts must wait 20 to 30 years to receive indefinite leave to remain.

Arrivals applying for indefinite leave to remain after 10 years must have no criminal record, speak English to A-level standards and have no debt, under Labour’s new proposals.

Ms Mahmood is being warned that the changes could lead to as many as 45,000 nurses leaving the UK, prompting calls for a dramatic increase in training for domestic staff.

Patient care could be plunged into crisis, with appointments cancelled, health groups warned.

The Home Secretary has also vowed to boot foreign criminals and migrants caught working illegally out of asylum hotels.

Net migration surged to a record high of 944,000 in the year ending March 2023. It hit 764,000 in 2022, before dropping to 649,000 in June 2024.

A staggering one in 30 people have arrived since 2021, with some 1.6 million people expected to receive indefinite leave to remain over the next five years, which would allow them to claim benefits and get a social home.

Many have warned of a financial time bomb if action is not taken.

The Royal College of GPs, while admitting the NHS is “heavily dependent on overseas recruitment”, said health chiefs must be able to continue employing overseas workers.

They told MPs: “As of October 31, at least 456 GPs have applied to the GMC this year for Confirmation of UK Training (CUKT), which is required by some other regulators for applications to work in their country.

“The RCGP has long argued that international GPs who successfully complete GP speciality training and gain entry to the GP Register should automatically qualify to apply for ILR.

“It is also integral to acknowledge that the NHS workforce is currently heavily dependent on overseas recruitment to fill workforce gaps, without which the service would struggle to operate.

“Without IMGs, many practices would be unable to maintain safe levels of patient access or meet contractual service requirements.”

Care England warned Labour’s current plans have created a new loophole which will allow workers to transfer to the NHS to circumvent the crackdown.

They told the Home Affairs Select Committee: “A provider raised that they have received their first resignation from a nurse who is leaving to join the NHS on the basis of the rule that an 'applicant has been employed in a specified public service occupation for five years, minus five years'.

“If this rule applies to NHS employment but not to social care roles, it would mean that nurses and any other roles that exist in both health and social care could secure Leave to Remain after five years by leaving their current employer and moving into the NHS.

“This was the reason provided for the resignation they have already received, and they anticipate a number of similar resignations once this becomes widely known.”