Rishi Sunak wants to find £50bn in tax rises and spending cuts to create a £10bn budget surplus.
The prime minister needs to prove that he can close the £40bn “black hole”, but is said to want to create a £10bn buffer to allow fiscal headroom.
The budgetary tightening of about 2% of GDP would be the equivalent of George Osborne’s 2010 austerity Budget.
The chancellor, Jeremy Hunt, has been in calls with previous Conservative chancellors going back to Osborne, as he prepares to drawn up his autumn statement, now expected on 17 November.
Many in Westminster and Whitehall are concerned about where the cuts will fall, saying there is no fat left to trim.
