07/06/2013 09:45 BST | Updated 07/06/2013 10:39 BST

Both 2015 And 2020 Will Be 'Austerity Elections', Voters Warned

File photo dated 8/5/12 of Prime Minister David Cameron (left) and Deputy Prime Minister Nick Clegg, who will insist today the coalition is "steadfast and united" as they mark the halfway point in their government with a raft of pledges on childcare bills, infrastructure investment and help towards care costs for the elderly.

Voters have been warned the public spending cuts begun under the coalition in 2010 could last for more than a decade, with both 2015 and 2020 being "austerity elections".

The bleak assessment came in a report compiled by the respected Institute for Government (IfG) and Institute for Fiscal Studies (IFS) think-tanks and presented on Friday.

The IfG and IFS said while the government has "held its nerve" in keeping departmental spending down, the lack of growth in the economy meant it was taking much longer than George Osborne expected to balance the budget deficit.

"Fiscal consolidation is taking longer than planned. The chancellor announced in the 2010 Emergency Budget that the budget deficit would be balanced within four years, but this is now forecast to happen in 2017-18," the report said.

"We are still as far away from the target as we were in 2010. Indeed, it would not be surprising if not just 2015 but also 2020 was an ‘austerity’ election."

The report added: "The problems for the consolidation have come through a lack of growth in the economy, resulting in lower than expected tax revenues."

The think-tanks also found that the public have become more willing to accept austerity measures as necessary.

The percentage of those who think that the Government is cutting spending too quickly has steadily declined from its level near 60% in early 2011 to 44% in May 2013.

However this should not be seen as a boost for the Conservatives and Lib Dems heading into the election - as voters do not think the coalition is cutting in a fair way.

The report comes as Osborne pressured Whitehall departments to accept a further 10% of spending cuts in order to free up money for infrastructure investment and the NHS.

In January Nick Clegg predicted 2015 would see the “first full blown scarcity election” as he set out how the Lib Dems would seek to occupy the centre ground between Labour and the Conservatives.

Clegg anticipated the 2015 campaign would be a "quite gritty realistic weighing up of options" rather than the "frothy happy-go-lucky" atmosphere of past elections.

If the IfG and IFS are right, that mood will continue to hang over the country for much longer.