Half of public sector managers surveyed say that they would struggle to identify efficiency savings, despite imminent budget cuts to be announced in the Government's Comprehensive Spending Review.
This is according to research by the Institute of Leadership & Management (ILM), which also found that two-thirds of bosses in the public sector do not feel fully prepared to deal with the cutbacks.
The vast majority (85%) of managers surveyed believe that cuts in the public sector will reduce the quality and level of frontline public services.
Penny de Valk, chief executive of ILM, said: "Managers will need to think strategically and make some difficult decisions if they are to achieve the savings required by the Treasury.
"Though a significant proportion of managers we surveyed recognised that efficiency savings could be implemented relatively easily, a high proportion feel there is little room for change."
More than a quarter (27%) of public sector managers surveyed say that they expect their jobs to be under threat following the spending review and nearly half (47%) believe that the changes will make their jobs harder or more stressful.
During a protest rally against the planned budget-cuts today, the TUC argued that the Government is ignoring credible alternatives.
Brendan Barber, TUC general secretary, said: "Economic experts across the spectrum warn us that the cuts are too deep and too rapid.
"At worst the cuts will plunge us back into recession. And at best they will condemn us to lost years of high unemployment and growth so weak that the deficit may well stay high."
The ILM surveyed 806 public sector managers of different levels from local government, health, education and other government departments.
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