Some of the most enthusiastic applause for David Cameron’s conference speech was sparked by an attack on a system that left a single mother of two on £150 ($238) a week with just 4p for every extra pound she earned.

“Thirty years ago this party won an election fighting against 98 per cent tax rates on the richest. Today I want us to show even more anger about 96 per cent tax rates on the poorest,” said the Tory leader.