It is “extremely unlikely” the government will hit its next target to reduce child poverty, the Institute for Fiscal Studies said on Thursday, even after Alistair Darling devoted what money he could spare to poor families with children.

In the Budget, Mr Darling boosted child benefit for the first child to £20 a week from April 2009, increased the generosity of child tax credits and said that in future the calculation of housing and council tax benefits would ignore child benefit in their means-tests. This package will cost taxpayers £870m in 2010-11.