The new Archbishop of Canterbury, Justin Welby, has condemned benefit cuts.
Backing a letter from UK bishops which criticised the government's decision to increase working-age benefits by only 1% - a real-terms cut at a time when inflation is at 2.7% - he said that society had a duty to protect the "vulnerable and in need".
The bishops claimed that 200,000 more children would be pushed into poverty by the changes, and many will be the children of unemployed people.
The Department for Work and Pensions (DWP) defended the cuts, saying it would help get people "into work and out of poverty".
A DWP spokesperson said "simply increasing benefits" would not tackle poverty, although it did not explain how cutting benefits would do so.
Labour's Yvette Cooper called the cuts "immoral" and said the Archbishop was "absolutely right" to speak out.
The benefit bill will be debated in the House of Lords next week, where bishops have asked for payments for children to be exempted from the below-inflation rise.
In a statement, Archbishop Welby said: "Politicians have a clear choice. By protecting children from the effects of this bill, they can help fulfil their commitment to end child poverty."
He said that the current system recognised the increasing costs of food, fuel and housing.
UnemployedNet campaigns for the government to use a Benefits Price Index (BPI) measure to increase welfare payments, and this would account for only the things that claimants actually buy.