Spending cuts: Government review set for 25 November
The government's spending review that will set out departmental budget cuts over the next five years will take place on 25 November.
The Treasury will write to cabinet ministers on Tuesday to ask for savings in their departments to total £20bn.
BBC Newsnight understands specific targets will not be set for departments.
It is expected that cabinet ministers will put forward their proposals for cuts by September.
The independent Institute for Fiscal Studies has calculated that departments that are not protected by a ring-fence will have to cut 12.6% from their budgets over the next five years.
'More with less'
Chancellor George Osborne announced £37bn of spending cuts during this parliament in his Budget.
He has already set out £17bn of cuts, including £12bn from welfare and £5bn from tackling tax evasion, avoidance, planning and imbalances in the tax system.
At the time he said that no year "will see cuts as deep" as those in 2011-12 and 2012-13.
Last month he ordered non-protected government departments to find £3bn in savings in the current financial year.
BBC Newsnight's Laura Kuenssberg said the theme of the November review would be "more with less".
She said Mr Osborne wants to encourage public sector reforms that use taxpayers' money more efficiently.
"The Treasury believes that billions can be found from selling off public land - they say currently more than £300bn's worth is owned by the taxpayer," she said.
"For the first time, departments will be expected to show they are contributing to the government's target of building 150,000 homes on land previously owned by the taxpayer by 2020."
She said ministers also believe that money could be released by devolving spending from Whitehall, under the Chancellor's so-called "Northern Powerhouse" strategy, which is a plan for increased devolution across England.
BBC Newsnight understands the previous process of the "star chamber" - where ministers appeared in front of a small cabinet committee to answer for their plans - will not be repeated.
However, ministers who engage with the Treasury as part of the process will have more control over where the cuts to the departments are made.