The Government today unveiled radical plans to get one million people off benefits and into work through a "something for something" culture.
Work and Pensions Secretary James Purnell said the plan was to "transform" the lives of people currently on benefits through additional help with training and childcare.
But he made it clear that a new sanctions regime would be launched to cut benefits from anyone refusing to take up training or the offer of a job.
Ministers were warned they faced growing concerns from backbench Labour MPs and pressure groups about the scale of welfare reform.
A White Paper will be published today outlining moves to expect virtually everyone to do something in return for their benefits, ranging from updating their CV to accepting full time training or a work trial.
The only exceptions will be carers, workless parents of very young children and severely disabled people.
Labour MPs who campaign on behalf of trade unions in Parliament said opposing the welfare reforms would be one of their main priorities in the coming months.
Mr Purnell gave a series of media interviews today to explain the reforms, stressing that the Government could not afford to waste taxpayers' money on people who were "playing the system".
He told BBC Radio 4's Today programme that virtually everyone would have to do something in return for their benefits, with the aim of helping them find work, improve their lives and turn around the "scars" left on communities by unemployment.
"Leaving people on benefit is the cruellest thing to do. We cannot afford to waste the talents of people," he said.
Mr Purnell said he had been approached by Labour MPs urging him to press ahead with the reforms, which he believed would help cut child poverty.
There would be "higher expectations" placed on jobseekers as part of the Government's target of moving one million off incapacity benefit (IB) by 2015.
He told BBC Breakfast News that IB claimants would be re-tested but added that more money would be given to those most in need.
Parents would be expected to look for work when their child reached the age of seven instead of the current 16, and to prepare for work before their child reached seven, said Mr Purnell.
The GMB union today urged Labour MPs to vote against the reforms. General secretary Paul Kenny said: "GMB has produced mounting evidence that the problem is a lack of demand from employers for these workers not the other way around."
Mr Kenny said it was a "total waste of time" trying to find "non existent" jobs for people employers did not want to take on.
John McDonnell (Hayes and Harlington) said: "The Government has got its priorities all wrong. It has allowed the bankers to get away with extravagant bonuses and yet is turning on the poorest and most vulnerable.
"It is lunacy to force people into jobs that are not there and to force lone parents to take up childcare which is either unaffordable or non-existent."
Radical changes to the welfare state recommended last year by city financier David Freud, such as paying private and voluntary groups to help get people back to work, would be implemented in full, the Government announced.
Mr Purnell added that the next wave of reforms would go "further and faster", adopting recommendations from a report it commissioned which called last week for unemployed people to do a 9-5 day looking for work or undertake community service-style duties such as digging gardens.
Couples claiming benefits where one of them did not have to actively look for work would be a "thing of the past", while new rules would be introduced for claimants who were drug addicts to make sure they tackled their problem or faced sanctions.