The Chancellor is expected to lay out his plans for curbing parts of public expenditure that are normally considered outside his control - the so-called Annual Managed Expenditure.
These include welfare, debt interest payments, tax credits and public sector pensions, which fluctuate over time and account for roughly half of all government spending.
The Times (£) reports that the Chancellor will target housing and incapacity and sickness benefits.
Shadow financial secretary to the Treasury Chris Leslie writes for ITV News in response to the Chancellor's Spending Review.
While the Conservatives and Lib Dem strategies are clear enough, Labour's response to government cuts is not yet obvious.
By excluding pensions and the benefits associated with the economic cycle, Osborne has put an automatic cap on a narrow range of benefits.