George Osborne and Iain Duncan Smith have insisted they will push ahead with plans to slash another £12bn a year from the benefits bill.
They reiterated their determination to achieve the savings in full after a major anti-austerity protest on the streets of London. Tens of thousands of protesters took to the streets, lighting fires and throwing smoke bombs as they demanded an end to the Government's austerity programme.
The crowd was addressed by Sinn Fein's Martin McGuinness, comedian Russell Brand and singer Charlotte Church, among others.
"Sinn Fein will not do Tory austerity. Unlike the Tory millionaires, I live in the heart of the proud working-class community of the Bogside in Derry," the Deputy First Minister said.
"The people the Tories are targeting are my friends, my neighbours, my family. They are fine, hard-working, proud and decent; just like our people in working-class unionist communities."
The Chancellor and Work and Pensions Secretary are believed to have thrashed out details of the cuts pledged in the Tory manifesto. They wrote in the Sunday Times: "For a start, we will reduce the benefit cap, and have made clear that we believe we need to make significant savings from other working-age benefits."
"We will set out in detail all the steps we will take to bring about savings totalling £12bn a year in next month's Budget and at the spending review in the autumn."