The work and pensions secretary has warned that unemployed people will be expected to undertake a work placement or voluntary role after a year of claiming benefits.
In a speech on welfare reform to the Social Market Foundation, James Purnell insisted that "avoiding work is not an option" for those claiming jobseeker's allowance .
He unveiled plans for a more flexible version of the welfare-to-work New Deal programme from October next year, which will link benefits to a "work-related activity".
Opposition parties were quick to dismiss the plan as a "half-baked" initiative that had already been previously announced.
Purnell said: "Our goal is to unlock the talent of all our people. We are today announcing a radical move to tackle worklessness.
"The message I want to send is clear - if you can work, you should work, and that will be a condition of getting benefits. But I recognise the genuine barriers that some people face.
"I want to help those long-term unemployed who need support and encouragement to build up their confidence and find work.
"But there are a small number of people who are determined not to work. Avoiding work is not an option."
Purnell will invite applications from the public, private and voluntary sector to run the programme.
His Conservative shadow Chris Grayling said the initiative had previously been unveiled last July, and was part of a string of 10 almost identical reform packages in two years.
"It's also very little different to what happens now under the New Deal," he said.
"If ever there was a sign of the failure of the government's policies, it's the fact that they feel the need to announce the same thing again and again."
Liberal Democrat work and pensions spokesman Danny Alexander said: "Evidence-based policy is being sacrificed for a desperate desire to sound tough.
"It is ridiculous to think that the threat of four weeks' work after a year or longer out of employment is going to make a difference.
"This rash of half-baked announcements is recognition of the government's failure to reform the welfare system over the last decade."
