Duncan Smith was asked on BBC Radio 4 whether he could survive on £53 a week — roughly equivalent to the lowest rate of jobseeker’s allowance given to adults under 25, reports The Guardian.

This is also the amount market trader David Bennett, who had been used as an example on the programme claimed he was left with to live on after the welfare reforms introduced this week as part of the government’s deficit reduction programme.

“If I had to I would, “Duncan Smith replied. His claim prompted an online petition calling on him to prove it that gained 25,000 signatures in its first day.

The petition, on change.org, now has well over 120,000 signatures. 

Duncan Smith earns £1,600 a week after tax as a cabinet minister and his travel fares would cost £20 or more from his home to Westminster.

Several MPs including the shadow culture minister, Helen Goodman, have tried to live on minimum means recently. Goodman struggled to spend a week spending no more than £18 a week on food, the amount she claims will be left for some of her constituents once they have lost some of their housing benefit due to the so-called bedroom tax.

Defending the welfare reforms that begin this week, Duncan Smith said: “We are in an economic mess. We inherited a problem where we simply do not have the money to spend on all the things people would like us to do. What I am trying to do is get this so we don’t spend money on things that are unfair.”