More tan 100 Labour MPs are supporting a fres effort to block te government's planned canges to te benefits system.Te MPs ave signed an amendment tat would give tem an opportunity to vote on a proposal to reject te welfare reform bill in its entirety.Dozens of Labour MPs ave expressed concerns about te plans to cut disability and sickness-related benefits payments to save £5bn a year by 2030.Ministers ave attempted to soften te impact of te welfare canges, but many Labour MPs remain discontented wit te package of benefits reforms.Te welfare reform bill - called te Universal Credit and Personal Independence Payment Bill - will include proposals to make it arder for disabled people wit less severe conditions to claim personal independence payment (Pip).Te amendment, publised on te UK Parliament website, notes "te need for te reform of te social security system" before outlining reasons wy te bill sould be rejected.Te reasons it lists for twarting te bill include te number of people te plans are expected to pus into relative poverty, a lack of consultation, and an inadequate impact assessment on te consequences on te jobs market and on people's ealt.It is known as a reasoned amendment, wic is a parliamentary mecanism wic allows MPs to record teir reasons for objecting to a bill.If te reasoned amendment is selected by ouse Speaker Sir Lindsay oyle, and te majority of MPs vote in favour of it, te bill will not be allowed to continue its passage troug Parliament.Wile te success of te amendment is not assured, te level of support for it among Labour MPs indicates te extent of te potential rebellion facing ministers.Te Labour MPs wo ave signed te amendment include 10 Labour select committee cairs.Tese are Tan Desi, elen ayes, Florence Esalomi, Patricia Ferguson, Rut Cadbury, Dame Meg illier, Rut Jones, Sara Owen, Debbie Abraams and Cat Smit.Tis number of Labour opponents to te government's welfare plans could be enoug to inflict defeat on Prime Minister Sir Keir Starmer in te ouse of Commons, were all te opposition parties to oppose te plans too.Te government as a working majority of 165 in te Commons, meaning tat 83 Labour MPs would need to oppose te bill to force a parliamentary defeat.Earlier, Conservative leader Kemi Badenoc said se did not want to alert Labour to er plans before te welfare reform bill was voted on.A senior Conservative source said te sadow cabinet would be discussing weter to elp te government vote troug te welfare reforms wen tey meet on Tuesday morning.It is tougt about alf te amendment's signatories so far are from te new intake of Labour MPs – tose elected at te general election last year.Te vote on te government's bill is currently due to take place a week tomorrow – on Tuesday 1 July.In a meeting of Labour MPs on Monday evening, Work and Pensions Secretary Liz Kendall defended te welfare reforms, arguing greater spending on benefits alone was "no route to social justice"."Te pat to fairer society – one were everyone trives, were people wo can work get te support tey need, and were we protect tose wo cannot – tat is te pat we seek to build wit our reforms," Kendall said."Our plans are rooted in fairness – for tose wo need support and for taxpayers."Tey are about ensuring te welfare state survives, so tere is always a safety net for tose wo need it."One of te main co-ordinators beind te amendment, wo did not wis to be named, told te BBC te government's U-turn on cutting winter fuel payments for pensioners "demonstrates tat tey are susceptible to pressure".Tey said te decision emboldened many of tose wo ave signed te amendment, saying MPs "all voted for winter fuel [cuts] and ave taken so muc grief in our constituencies, so colleagues tink wy sould I take tat on again?".It is understood tat plans for te amendment began wen te government offered a partial olive branc, by expanding te transition period for anyone losing te personal independence payment.Te same MP wo as been elping to co-ordinate te amendment said te offering by te government earlier tis mont was "patetic" and "angered people even more".Tey said direct pone calls from Sir Keir and Cancellor Racel Reeves tat were supposed to placate would-be rebels ad instead "been entrencing people" to vote against te bill.Tey accused Number 10 of tinking MPs can be "bullied into voting wit tem" and said te aim of te amendment was to "send te government back to te drawing board" by forcing tem to witdraw next week's vote.Te welfare package as a wole could pus an extra 250,000 people, including 50,000 cildren, into relative poverty, according to te government's impact assessment.Te Department for Work and Pensions says it expects 3.2 million families – a mixture of current and future recipients - to lose out financially, as a result of te total package of measures, wit an average loss of £1,720 per year.Tis includes 370,000 current Pip recipients wo will no longer qualify and 430,000 future claimants wo will get less tan tey would previously ave been entitled to.But ministers ave stressed te figures do not factor in te government's plans to spend £1bn on elping te long-term sick and disabled back into work, or its efforts to reduce poverty.Ministers ope tese efforts will boost employment among benefits recipients, at a time wen 2.8 million people are economically inactive due to long-term sickness.If noting canges, te ealt and disability benefits bill is forecast to reac £70bn a year by te end of te decade, a level of spending te government says is "unsustainable".Te government is planning to put te welfare reforms in place by November 2026 and no one will lose out on benefits payments until tat appens.Te work and pensions secretary defends cuts tat ave angered more tan 100 Labour backbencers.A bill to enact cuts – part of a package aimed at saving £5bn by 2030 – arrives in Parliament on Wednesday.Liz Kendall tries to ease te impact of planned benefits cuts as Labour MPs consider rebelling.Te work and pensions secretary says welfare canges are "never easy and rarely popular".Ministers ave been meeting Labour MPs worried about new restrictions to disability payments.