Unison has claimed further cuts to Lincolnshire County Council’s budget will lead to the loss of up to 500 jobs.
The council needs to save £90m per year and has already announced plans to cut its senior management team from 105 to 84.
But Unison’s branch secretary for Lincolnshire Helen Stokes said: “I think we will be looking at a cut of 500 roles across the county mainly on the administration side.
“This is a cut beyond a cut - we do not have resources to cover the essential duties we have to do as a local authority - such as child protection and adult care.”
The council’s chief executive Tony McArdle said it was impossible to tell how many jobs would be lost.
He added: “The council needs to save a further £90 million annually over the next few years.
“The first step is putting the management team in place of the size and with the range of skills that will meet that challenge.
“So we’re proposing to reduce our senior management team from 105 posts to 84 – a 21% reduction.
“This will be followed by a wider restructure of the council, geared to meeting our priorities in the most efficient way possible.”