The UK Government is to formally drop its ill-fated cuts to disabled benefits in the wake of Iain Duncan Smith’s dramatic resignation.

New work and pensions secretary Stephen Crabb will tell the Commons in a statement on Monday that the curbs to Personal Independence Payment (PIP) have been abandoned.

The move comes after a turbulent day of Tory infighting that saw Mr Duncan Smith condemn Chancellor George Osborne’s “arbitrary” cap on welfare spending and obsession with “short term savings”.

Speaking on the BBC’s Andrew Marr show, the former Conservative leader insisted his decision to quit the Cabinet was not “personal” or a “secondary attack” on the Prime Minister.

He said he felt the party was undermining its “one nation” ambitions by balancing the books on the back of the working age poor and vulnerable. The final trigger for his resignation was learning that Mr Osborne had “juxtaposed” the £1.3 billion a year PIP curbs with tax cuts for the better off in the Budget.

“The truth is yes, we need to get the deficit down, but we need to make sure we widen the scope of where we look to get that deficit down and not just narrow it down on working age benefits,” Mr Duncan Smith said. “Because otherwise it just looks like we see this as a pot of money, that it doesn’t matter because they don’t vote for us.”

Mr Duncan Smith flatly denied that his decision had anything to do with personal animosity to Mr Osborne or his desire for Britain to leave the EU, describing that as “the most puerile idea I have ever heard”.

he Scottish National Party has today described Iain Duncan Smith’s resignation as a “distraction” from the real issue of cuts to the welfare and disability budget.

Stewart Hosie MP, Economy spokesperson and Deputy Leader of the SNP, called for the cuts to be “immediately and completely” scrapped.

He said: “Iain Duncan Smith’s crocodile tears are a distraction from the real issue at hand – while the deep divisions at the top of the Tory party widen and the mud-slinging continues, disabled people and those on low-incomes are still expected to bear the brunt of the Tories’ obsession with austerity.

“The UK government was warned that slashing £12 billion from the welfare budget would do real and lasting harm but the Tories are determined to plough on, cutting even more from the disability budget. What this resignation proves beyond doubt is that the Tories’ must abandon their ideological commitment to austerity cuts.”

UK Pensions minister Lady Altman accused her old boss of “shocking” behaviour and trying to inflict “maximum damage” on the party leadership to get Britain out of the EU. Shadow chancellor John McDonnell insisted Mr Osborne now had to “rip up” the financial package.

“George Osborne needs to come back to Parliament now, pull this Budget and start again because this Budget isn’t sustainable any more,” he told BBC Radio 5 live. Labour is likely to table an urgent question in a bid to force the Chancellor to come to the Commons. Prime Minister David Cameron is also due to make a statement to MPs on last week’s Brussels summit, where a new deal aiming to tackle the migrant crisis was agreed.