Ministers insisted last night that they had enough money to implement new tests on all incapacity benefit claimants after Conservative claims of a “con”. Disability charities also voiced concerns about people being “thrown off” benefits under the scheme.

James Purnell, the Work and Pensions Secretary, said yesterday that all 2.6 million benefit claimants will be forced to undergo tests from 2010 to prove that they are unfit. The Conservatives said that money allocated in the Budget for the tests was insufficient.

Mr Purnell gave warning that for people who did not play by the rules there would be “clear consequences” for their behaviour.

“For those who play by the rules we will provide extra support so they can realise their ambitions,” he said in the Commons.

Chris Grayling, his Conservative shadow, said that only £10 million extra had been put aside to pay for assessments – not even enough to cover reassessments for 16-24 year olds announced last November.

“That will leave 94 per cent of current claimants – some 2.5 million people – outside the Government’s plans. There is no money set aside to pay for them to have assessments, and no money to pay for expanded back-to-work programmes of the kind in use in countries like the United States.”

Describing the announcement as “the worst kind of political fraud”, Mr Grayling added: “When you read the small print, it is simply not true. The money being set aside amounts to less than £4 per claimant – enough to pay for their bus fares to the local job centre and nothing more.

“It will cause considerable disquiet among incapacity benefit claimants, without giving them any promise of extra support to get back into work. It is designed to create headlines, without the Government actually having to deliver the kind of radical welfare reform that this country needs.”

Officials insisted that the total allocated for testing in 2010 was £30million, with a further £20million coming from departmental savings. In addition there was already money in the system for reassessing of claimants.

They added that it would take three years for all the claimants to undergo the tests, and that there was sufficient money for that to happen.

Meanwhile, charities voiced worries. Paul Treloar, the director of policy and services at the Disability Alliance, said that his charity supported efforts to help disabled people into work, but said it was “dishonest” to use a more stringent test simply to reduce the number of claimants.

Moving the bar higher to claim incapacity benefit was not a solution, he told the BBC.

“When people have been on incapacity benefit for significant periods of time, simply moving them to the job-seekers’ allowance is not going to help them back into work.”

He said that, in his experience, “it does cause concern when people think there are intentions simply to throw them off benefits”.

Kevin Doherty, the director of services at Disability Action, added that the “overall ethos” of the vast majority of those claiming incapacity benefit was the desire to work.

He called for “creative programmes and initiatives to be introduced to the overall working environment”.

Vince Cable, the Liberal Democrats’ Treasury spokesman, accused Labour and the Tories of “dishonesty and naivety” in “imagining people who want to work are being barred from doing it because of the benefits system”.

Many of those claiming incapacity benefit were mentally ill and were unable to seek employment.

I would love to work again but I’ve been in too much pain

Tracey Follis, 28, suffers from osteochondritis dissecans lesions (OCD) of the knee, causing her great pain when she walks or stands.

She worked as a carer for eight years while suffering from the disease, but two years ago was told to have an operation, which has only exacerbated the problem. She has not worked since.

She thinks that government plans announced in the Budget to subject people who claim incapacity benefit to an eligibility test are insulting.

She says: “It makes me feel like I am doing something wrong by claiming incapacity benefit. I would love to work again, but ever since I had my operation I’ve been in too much pain.”

A cocktail of six drugs helps to relieve her symptoms, but she struggles to pay for the prescriptions, as well as living costs, on the money she gets from the Government. She is currently given £98 a week in incapacity benefit.

“Thankfully, I’ve got a partner who works full-time to keep a roof over my children’s heads,” she says.

Ms Follis, who lives with her partner, Mark Bennett, 28, and two children, Megan, 7, and Leah, 3, attends courses at the Birmingham Disability Resource Centre in the hope of returning to work.

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