Plans for a £500-a-week cap on household benefits have been condemned as "immoral" by a former Liberal Democrat minister in an escalation of her criticism of the welfare reform.
Sarah Teather accused ministers of seeking to "gain popularity at the expense of children's lives" by pushing through a measure they knew was popular but ineffective.
The Lib Dem faced calls for her sacking as children's minister in February after she missed a key vote on the reforms, which she had publicly questioned.
She eventually departed from government ranks in September's reshuffle.
Speaking to The Observer, she said: "I think deliberately to stoke up envy and division between people in order to gain popularity at the expense of children's lives is immoral.
"It has no good intent."
She went on: "There are all sorts of things you have to do when times are tight that have negative consequences but you do them for good purposes.
"But to do something for negative purposes that also has negative consequences - that is immoral."
She added: "I don't think it was even remotely conceived as a financial cost-cutting device. I think it was conceived as a political device to demonstrate whose side you are on."
She said she was "terrified" about the prospects for many families who would be forced to move to cheaper areas where they would find it harder to find work.
"My fear is that a lot of people will effectively just disappear from the area in which they were living. I think some very horrible things are going to happen," she said, questioning how well child protection and education services would keep track of youngsters.
A spokesman for Work and Pensions Secretary Iain Duncan Smith accused her of hugely misinformed scaremongering.
"The criticisms Sarah Teather is levelling against the Government's welfare reforms are hugely misinformed and therefore result in needless scaremongering," he told the newspaper.
"It's not fair or right that benefits claimants receive higher incomes than hard-working families who are striving to get on in life. Our reforms bring fairness back to the system while ensuring we support the most vulnerable."
Business Secretary Vince Cable said his party colleague was right to warn of the risks of "very serious social consequences" but defended the need for a cap.
It was required to prevent housing benefit "escalating out of control" but had to be accompanied by an increase in the provision of affordable housing, he said.
"What is immoral, and I have read her article carefully, is demonising poor people."
He told BBC1's Andrew Marr Show: "We have got to cap the housing benefit element while at the same time increasing the supply of affordable housing.
"That is absolutely critical because without that you will have very serious social consequences which Sarah has quite rightly warned about."