People with mobility and mental health problems will be asked to work from home or lose their benefits.
The policy will be set out tomorrow as part of the autumn statement amid a drive by Rishi Sunak, the prime minister.
He deems it necessary to make changes to the welfare system, which he described on Monday as “unsustainable.”
Hundreds of thousands of people will be told to look for work that they can do from home or face having their benefits cut by £4,680 a year.
Laura Trott, chief secretary to the Treasury, said: “There should be support for people to help them into work but ultimately there is a duty on citizens if they can go out to work they should. Those who can work and contribute should contribute.”
She added: “You have to engage with that, and that is an obligation on you as a citizen to do this. And if you don’t do this, we will look at sanctions.”
The prime minister said: “We believe in the inherent dignity of a good job. And we believe that work, not welfare, is the best route out of poverty.”
“Yet right now, around 2 million people of working age are not working at all. That is a national scandal and an enormous waste of human potential. So, we must do more to support those who can work to do so.”
The number of people on health-related benefits has risen by a quarter since the eve of the Covid pandemic. Most of these are in the limited capability for work-related activity group, who receive the additional £390.06 a month.