In an opinion piece in The Daily Telegraph, Duncan Smith said the system discourages "incentive, opportunity and responsibility."
Chancellor of the Exchequer George Osborne and Duncan Smith were said to be planning to announce a freeze on jobless benefits and 3 billion pounds ($4.80 billion) in cuts in the system, the Telegraph said. The chancellor is scheduled to make his Autumn Statement on Wednesday.
"We need to restore confidence in the system, so people trust that it will be there when they need it, but that it will not pay for a life on benefits when work is available," Duncan Smith said in the Telegraph.
The cuts would not affect retirees, the Telegraph said.