Supermarket chain Tesco has amended a job advert looking for permanent workers in exchange for expenses and jobseeker's allowance, saying it was a mistake.
Twitter and Facebook users had highlighted the advert for a night shift worker at a store in west Suffolk on the Jobseekers' Plus website.
The job was offered under the Government's "workfare scheme" which is linked to payment of benefits - but Tesco said the impression that it was seeking to replace full-time workers was mistaken.
The error comes after unions called for high street chains to withdraw from Government programmes that require the unemployed to work for up to six months or face losing their benefits.
A statement from the supermarket chain said: "The advert is a mistake caused by an IT error by Jobcentre Plus and is being rectified.
"It is an advert for work experience with a guaranteed job interview at the end of it as part of a Government-led work experience scheme.
"We take our responsibility as Britain's biggest private sector employer seriously."
The company defended its involvement in the scheme, saying that such work experience could be valuable.
So far, 300 young people have gone on to get permanent employment after a placement, the statement added.
Such placements were not "a replacement or substitute for our permanent staff".
The statement added: "In general, Tesco staff receive a higher level of basic pay than any other supermarket, without exception."
Shopworkers' union Usdaw, which represents more than 400,000 workers in high street stores, said it was in discussions with major retailers about their involvement, saying that while work experience could be valuable, schemes should be voluntary and pay the going rate.
Sainsbury's and the Waterstones book chain have already withdrawn from the scheme.
Employment Minister Chris Grayling told the Commons last month that the scheme was working well and was much better value for money for the taxpayer than the last Labour government's Future Jobs Fund.
Jobseekers' allowance is currently paid at £53.45 per week for under-25s, or £67.50 for older staff.