Iain Duncan Smith has been urged to suspend his controversial benefit sanctions until a review is carried out of their impact, particularly on the mentally ill and disabled.
Experts, ranging from academics, food bank administrators, disabled groups and employment service professionals, told MPs on the work and pensions select committee on Wednesday how sanctions were "more likely" to hinder their target's journey into work, rather than help them.
Duncan Smith's sanctions, under which a jobseeker can automatically lose their benefits for low-level offences like missing an interview with their Jobcentre adviser, have been a subject of mounting controversy as critics warned that the "immoral" reforms would drive people to rely on food banks to survive.
The Department for Work and Pensions (DWP) has so far defended the regime, with senior official Neil Couling causing controversy after he argued that sanctions can provide a "welcome jolt" to those affected.
A spokesman for the Public and Commercial Services Union told the Huffington Post UK: "There's no evidence that sanctions spur people into finding sustainable work, All they do is poison the relationship between jobcentre staff and claimants, which makes it much more difficult to build the kind of relationship that is required.
"A jobcentre should be a place that supports people into finding a job, not a place of conflict and suspicion."
A DWP-commissioned review, carried out by welfare expert Matthew Oakley, who has worked for the Treasury and the centre-right thinktank Policy Exchange, revealed that the most vulnerable were often left punished by a system that they barely understand.
Questioned by MPs on Monday, Oakley, who reviewed the sanctions system, said ministers should review its impact as the government lacked information on what happened to claimants who were affected.
Tony Wilson, from the Centre for Social and Economic Inclusion, said sanctions “are running so far ahead of what works we should suspend the applications of sanctions unless we have a much clearer idea of what works and the impact of sanctions”.
Kirsty McHugh, the chief executive of Employment Related Services Association, the representative body for the employment support sector, also called for an overhaul including the introduction of an “early warning” system which could be used at first offence rather than imposing a sanction.
She added: “For a minority of people, receiving a sanction can be the wake up call they need to help them move into work. However, for the vast majority of jobseekers, sanctions are more likely to hinder their journey into employment.”
In response, a DWP spokesman told HuffPostUK: "Jobcentre Plus advisers work hard every day to help people into work and sanctions are only used in a small minority of cases where benefit claimants don’t hold up their end of the bargain to look for work.
“Decisions aren't taken lightly and we have a well-established system of hardship provision for vulnerable claimants. The number of sanctions has gone down over the past year”
See more on the 2015 General Election here