Work and pensions secretary Peter Hain dismissed last week's newly unveiled welfare plans from the Tories as a "PR gimmick".
Making anyone who has been claiming benefits for two years or more take part in a year-long "community work programme" would not move them into real jobs and was not backed up by new funding, he insisted.
"However, the Government's flexible New Deal will see private and voluntary providers being paid to move more people into sustainable jobs," he added.
"Instead of PR gimmicks, our focus on training and work-trials backed by tough expectations on claimants is what will move people into real jobs."
Shadow secretary Chris Grayling said the Conservatives' Work for Welfare green paper aimed to stop people making "a career of claiming out-of-work benefits". He also wanted them to compete more for jobs with migrants.
"It makes no sense to have millions of people coming to Britain to work while we have millions of people stuck at home," he said.
The Institute for Public Policy Research think-tank said similar hawkish policies in the US denied benefits instead of securing jobs.