Former work and pensions secretary Stephen Crabb has called for further changes to controversial welfare reforms.
Mr Crabb said the assessment process for personal independence payments (PIP) needs improving for disabled people.
The former cabinet minister, who resigned from the Government as Theresa May formed her team in July, spoke out a week after his successor Damian Green launched a consultation on reform of the Work Capability Assessment, used to apply for Employment Support Allowance.
Mr Crabb told BBC Wales's Week In Week Out programme he is not opposed to PIPs, but he believes changes are necessary.
"They feel it's been a very intrusive, invasive kind of assessment - and that's not what we're trying to do," he said.
"We need to have a supportive assessment process that obviously comes to the right decision about the kind of money and resource that a disabled person needs."
PIPs were introduced in 2013 and are paid to disabled people to help them live an independent life.
As secretary of state, Mr Crabb scrapped plans to cut PIP benefits and his predecessor Iain Duncan Smith resigned over those proposed cuts in the Budget in March.
Mr Crabb, MP for Preseli Pembrokeshire, said: "Iain Duncan Smith had resigned, there was a great big row going on about proposed cuts to PIPs.
"I thought it was wrong. I wasn't willing to step into the job to make my first act one of cutting support for disabled people. So I did make it a condition that we wouldn't be going ahead with those cuts.
"Of course you do need a system of assessment when you're giving out taxpayers' money. You need some kind of system to determine who needs it and who needs it most, but the way it has been done - I see this in my surgeries, every single MP in their surgery sees this - people who felt that the assessment procedure has been traumatic, intrusive, hasn't been a comfortable experience at all. And that's what we've got to fix."
:: The interview with Mr Crabb features on Week In Week Out: Why Have My Benefits Been Cut? on BBC One Wales at 10.45pm on Tuesday.