The announcement comes just under two months since Mr Crabb said the Government had “no further plans” for specific welfare cuts.

Mr Crabb, who replaced Iain Duncan Smith in the role in March, said he would set out a green paper on further proposed changes to disability benefits later this year.

“The measures that have either already been legislated for or announced get us to the £12 billion [welfare cuts planned in the Conservative manifesto],” he said.

“Does that mean welfare reform comes to an end? I would say no. I’ve already pointed to what I see as one of the big challenges of welfare reform – and that’s around work and health.”

Mr Crabb told MPs on Work and Pensions Select Committee that he would deploy “smart strategies” for cutting expenditure on disability and sickness benefits and would hopefully be able to secure the support of disability charities.

“In terms of how you make progress of welfare reform there when you are talking about people who are very vulnerable, people with multiple barriers, challenges, sicknesses, disabilities – I am pretty clear in my mind that you can’t just set targets for cutting welfare expenditure,” he said.

“When you’re talking about those cohorts of people you’ve actually got to come up with some pretty smart strategies for doing it which carry the support and permission of those people and organisations who represent those people who we are talking about.

“This is why there’ll be further information in due course about this. I want to produce a green paper later this year which starts to re-frame discussion around this set of issues.”

The Government has already make sharp cuts to the Employment and Support Allowance disability benefit, cutting the rate for new claimants in the Work Related Activity Group by £30 a week from 2017.

It has also abolished the Independent Living Fund and make reductions to payments for the Access To Work scheme.

Ministers backed down on cuts to the Personal Independence Payment after the resignation of Mr Duncan Smith, who warned that the Government was paying for deficit reduction by hurting the most vulnerable in society.

Economists, including the Institute for Fiscal Studies, have previously reacted with skepticism that the previously announced £12 billion welfare cuts were achievable – especially after cuts to PIP and tax credits were dropped or delayed.

Labour’s shadow work and pensions secretary Owen Smith said the Government should reverse the ESA cuts which had already been passed, adding that the Government needed to offer clarity on how it would support disabled people into work..

“The flimsy case for the cuts to Employment Support Allowance is now totally blown apart by this broken promise and the Tories must listen to Labour’s calls for them to be reversed,” he said.

The Independent has asked to DWP to clarify whether it is planning further specific disability benefit cuts.