Intervening on Work and Pensions Secretary Iain Duncan Smith in the Commons, his Labour shadow, Helen Goodman asked: “Could you explain to the House why cutting tax credits for large families is a fair thing to do when it will be concentrated… on families where children are living in poverty, on Roman Catholic families, on Catholics from other minorities.

“Don’t you understand that every child matters?”

Mr Duncan Smith replied: “I have for some time believed the way tax credits operated distorted the system so there were far too many families not going into work, living in bigger and bigger houses, with larger families subsidised by the state when many others, the vast majority of families in Britain, make decisions about how many children they can have and the houses they can live in.

“Getting that balance back is about getting fairness back into the system.”