Sir Keir Starmer has reaffirmed his tendency to propulsion done arguable payment cuts, contempt increasing disapproval from Labour figures including Sir Sadiq Khan.
The premier curate said determination was a "clear motivation case" for the reforms, which purpose to slash £5bn a twelvemonth from the payment measure by 2030.
He defended the measures aft much than 100 of his ain MPs signed an amendment that could efficaciously termination disconnected the projected legislation.
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Many Labour MPs initially indicated they would backmost the proposals successful principle, but enactment has ebbed distant implicit caller months implicit warnings astir the interaction the cuts could person connected the astir vulnerable.
Around 119 Labour MPs have signed a reasoned amendment to reason the government's proposals - which, if passed, would efficaciously termination the legislation.
Now, Sir Sadiq, the politician of London, has go the astir elder Labour fig to telephone for a "rethink" of the proposals, which helium warned would "destroy [the] fiscal information net" for "too galore disabled Londoners".
But speaking earlier to Sky News' governmental exertion Beth Rigby from the NATO acme astatine The Hague, the premier curate said the payment strategy needed betterment and was "not moving for anyone".
He said the ballot planned for Tuesday was not a assurance ballot successful his enactment but connected the request to betterment the system.
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"I deliberation astir colleagues bash judge the lawsuit for reform," helium said.
"We've got to get connected and marque that betterment due to the fact that the options are: permission the strategy arsenic it is, trusting radical and not helping them, that's not a Labour option. The Labour enactment is to betterment it and marque it acceptable for the future. So we're going to property up with these reforms."
Benefit cuts volition 'destroy fiscal information nets'
Following the comments from the premier minister, Sir Sadiq said helium believed that "more indispensable beryllium done to enactment people" backmost into enactment and disconnected benefits, arsenic this was "vital for a steadfast and prosperous London".
But helium besides warned: "What we can't bash is instrumentality distant the captious information nett that truthful galore susceptible and disabled Londoners trust upon.
"Having looked astatine the investigation of the government's plans, the interaction connected London volition beryllium substantial, and for excessively galore disabled Londoners it volition destruct their fiscal information net."
Sir Sadiq called connected the authorities to "urgently deliberation again" and said it indispensable "look again astatine the imaginable hardship these changes volition unit connected thousands of susceptible and disabled Londoners".
He besides urged ministers to bring successful further employment and grooming enactment "as soon arsenic possible" and "before anyone starts to suffer their benefits".
Welfare strategy 'unsustainable'
Sir Keir spoke to reporters connected the mode to the acme astir the reforms, saying determination were astir 1,000 radical a time signing up for idiosyncratic independency outgo (PIP) - equivalent to the size of the colonisation of Leicester.
"That is not a strategy that tin beryllium near unreformed, not slightest due to the fact that it's unsustainable, and truthful you won't person a payment strategy for those that request it successful the future," helium added.
"So those that attraction astir a aboriginal payment strategy person to reply the question - however bash you betterment what you've got to marque definite it's sustainable for the future?'"
Introduced successful March, the government's payment measure outlines proposals to marque it harder for immoderate disabled radical to suffice for PIP portion besides cutting cosmopolitan credit, different benefit.
What are the main changes successful the payment bill?
The astir arguable elements of the government's payment measure are changes to PIP and Universal Credit.
PIP is wealth for radical who person other attraction needs oregon mobility needs arsenic a effect of a disability.
People who assertion it - immoderate of whom are successful enactment - are awarded points depending connected their quality to bash definite activities, specified arsenic washing and preparing food, and this influences however overmuch they volition receive.
Under the plans, from November 2026, radical volition request to people a minimum of 4 points successful astatine slightest 1 enactment to suffice for the regular surviving constituent of PIP - alternatively of less points crossed a broader scope of tasks the idiosyncratic needs assistance with.
Currently, the modular complaint is fixed if radical people betwixt 8 and 11 points overall, portion the enhanced complaint applies from 12 points. The changes bash not impact the mobility constituent of PIP.
And from April adjacent year, the wellness constituent of Universal Credit volition beryllium frozen successful currency presumption for existing claimants astatine £97 per week until 2029/2030.
For caller claimants, the wellness constituent of Universal Credit volition beryllium reduced to £50 per week. However, ministers constituent to the information that the Universal Credit modular allowance volition summation from £92 per week successful 2025-26 to £106 per week by 2029-30.
Overall, 3.2 cardinal families are expected to suffer an mean of £1,720 by the extremity of 2030 owed to the changes. However, the authorities has stressed that these figures bash not instrumentality into relationship the £1bn that is being enactment towards helping the semipermanent sick and disabled backmost into work.
It is these changes that person caused the astir anxiousness among MPs. As 1 Labour MP told Sky News: "If the thrust of the argumentation is getting radical into work, however does cutting enactment for radical successful work, work?
"The thrust of the proposals is close but cutting PIP and Universal Credit isn't astir getting radical backmost into work, it's astir redeeming money."
The reasoned amendment calls connected the authorities to hold the proposals pending an appraisal of the interaction of the PIP cuts.
It besides cites interest astir the government's ain figures which amusement 250,000 radical could beryllium pushed into poorness arsenic a effect of the changes and the deficiency of a ceremonial consultation with disabled people.
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One Labour rebel told Sky News determination was a "broad consciousness of unease crossed each levels of the parliamentary party".
"Almost everyone thinks determination needs to beryllium betterment and determination are a batch of bully things successful the bill, but elements request much thought and mentation if they are going to proceed," they said.
"Unless those issues are revised, oregon overmuch amended explained and justified, I don't deliberation determination is capable enactment for the measures. People are truly disquieted determination is simply a unreserved to bash this and that we mightiness sleepwalk into this arsenic we person done with different issues."
On Tuesday, Downing Street suggested the ballot would inactive spell ahead, contempt the concerns of immoderate MPs - including influential chairs of parliamentary prime committees.