The Treasury has reached deals with seven more government departments on their spending cuts for the next five years.
The departments will face average cuts in day-to-day spending of 21% by 2019-20, worth more than £2.5bn per year.
The Department for Work and Pensions is one that has reached an agreement, along with the Department of Energy and Climate Change, HMRC, Cabinet Office, Scotland Office, Wales Office and Northern Ireland Office.
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The agreement comes after Iain Duncan Smith allegedly threatened to resign as work and pensions secretary if chancellor George Osborne tried to adjust the earnings taper for Universal Credit to fund mitigating measures for those hit by his proposed £4.4bn cuts to tax credits.
The Sunday Times reported over the weekend that Osborne would now seek deeper cuts in housing benefits as he aims to meet his pre-election pledge of cutting the welfare budget by £12bn, but it is not clear whether this is the agreement he came to with Duncan Smith.
Over half of the main Whitehall departments have now reached provisional agreements on their resource budgets, which are set to deliver more than £4bn of savings by 2019-20.
The Home Office is yet to agree a deal with the Treasury, amid reports that home secretary Theresa May and London mayor Boris Johnson are urging Osborne to protect policing from further cuts. The Foreign Office is also still to settle ahead of next Wednesday's statement from the chancellor.