The scale of the Conservatives' planned spending cuts after 2015 would mean the role of the state would change "beyond recognition", the head of the Institute for Fiscal Studies has said.
The IFS said £35 billion of the cuts in spending by Whitehall departments have already happened, with £55 billion yet to come.
If reductions in departmental spending were to continue at the same pace after the May 2015 election as they have over the past four years, welfare cuts or tax rises worth about £21 billion a year would be needed by 2019/20 - at a time when Conservatives are committed to income tax cuts worth £7 billion - said IFS director Paul Johnson.
Mr Johnson said voters would be justified in asking whether George Osborne was planning "a fundamental reimagining of the role of the state".
The Chancellor must tell voters whether what he's proposing is really a re-think of the role of the state.
For all the criticism of spending reductions under the Coalition, there are actually more cuts to come after 2015.
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