Parents on benefits who have more than two children could be penalised as part of the government drive to find further cuts in welfare, Iain Duncan Smith has said.
The Conservative work and pensions secretary is expected to use a speech at the Cambridge Public Policy thinktank to say that some parts of the benefits system promote "destructive" behaviour.
He will lay the ground for a fresh assault on the welfare budget and renew warnings that parents on benefits should not automatically expect more cash if they have more children. George Osborne intends to slash another £10bn from the welfare bill by 2016/17 on top of the £18bn already being cut.
Duncan Smith insisted on the BBC Radio 4 Today programme before his speech that there were large numbers of people having children who had no intention of getting a job, pointing to the "clustering" of large families on the very lowest incomes – "those on significant levels of welfare" – as well as those on the very top income.
This was because families on average incomes had to decide how many children they could afford, and families living on benefits should be forced to make the same decisions, he said.
He suggested that reforms were likely to kick in if a parent on benefits went on to have a third child. He said that it was no surprise that the country was "in massive debt and huge deficit because we are not paying our way", but he went on to say that further reforms were not just about savings but also providing fairness to taxpayers.
He said: "My view is that if you did this you would start it for those who begin to have more than say two children. Essentially it's about the amount of money that you pay to support how many children, and what is clear to the general public, that they make decisions based on what they can afford for the number of children they have. That is the nature of what we all do."
"It's not about hurting," he said. "It's about saying we have accepted far too long in this country that it is possible just to stay on benefits, that we write them off, and we work only with those who get up in the morning and go to work. And that's simply not acceptable. It's not acceptable because it destroys their lives. It also destroys the lives of taxpayers who have to pick up that bill to pay for them. It's no surprise that we are in massive debt and huge deficit because we are not paying our way. All of that is the consequence of years of simply saying it's too difficult, these people should be left as they are and the rest will do all the work."
He added: "This is not just about the money. It's also about those children growing up in workless households. Their lives are destroyed by this. They need also to learn that it's the right thing for parents to go to work."
Alison Garnham, the chief executive of Child Poverty Action Group, expressed concerns about the signals being sent out about parents on benefits. She said six out of 10 poor children lived with a working parent on low pay, such as a cleaner or care worker.
"Like many other people, when they [parents] plan their families they're not thinking about whether at some point in future they might be on benefit. I think some of the things that are being talked about today are a bit worrying, for example the implication that people don't want to take jobs when, in fact, we know, if you look at the jobseeker's allowance figure, you will see that most people, 90%, have left jobseeker's allowance between six to 12 months, so there's no evidence that people are not willing to take jobs."
She also rejected government suggestions that there were large numbers of people who did not want to work.
She said: "I don't think it's that they don't want to work. Those are people probably with multiple problems. They have issues about skills, some have health problems and so on, so I don't think it's a simple picture for that group either. There are always people that we disapprove of but I think it's best to look at the facts. In the majority of cases that is not what is going on. What we're seeing is people cycling in and out of benefits because of the state of the labour market. Many of the jobs they go to are short-term, insecure and very low-paid and they find themselves back on benefits shortly afterwards, so there's no unwillingness to work."
Gingerbread, the charity for one-parent families, warned that a cap on child-related benefits for families with more than two children would have a "devastating impact" on children.
Fiona Weir, the Gingerbread chief executive, said: "The reality is that many parents will find themselves cycling in and out of work as stable, well-paid jobs are difficult to come by. Families cannot be expected to predict the future state of the economy and adjust their family size accordingly.
"Instead of penalising families, the government must focus on providing real solutions to get more people into work, such as affordable childcare, more flexible working options for today's modern families and ensuring that the welfare system supports people into work and out of poverty."
Duncan Smith is expected to say in his speech that all too often, the government's response to social breakdown has been "patching": "a case of handing money out, containing problems and limiting the damage but, in doing so, supporting – even reinforcing – dysfunctional behaviour".
He will add: "You have to ask which bits of the system are most important in changing lives. And you have to look at which parts of the system promote positive behaviours and which are actually promoting destructive ones."
The minister is expected to refer to warnings from the welfare state founder William Beveridge that recipients should not expect to benefit "from a bottomless pit" of funds.
The shadow work and pensions secretary, Liam Byrne, said: "Iain Duncan Smith is destroying Beveridge, not renewing Beveridge. For all the tough talk the truth is it's working people who are seeing their help axed. Never before have working people paid so much in and got so little back. Yet this government sees fit to give £40,000 to 8,000 millionaires in tax cuts, yet is cutting tax credits so hard that thousands are now better off on benefits.
"We were promised a welfare revolution and all we've got is welfare chaos – chaos that working people are being forced to pay for."
