Unison has defended the retirement provision for nurses after the Liberal Democrats vowed to consider reforming the sector's "generous pension system".
Pensions spokesman Danny Alexander warned there is a growing gulf between the "high-quality" pensions enjoyed by many state employees, and those available to the rest of society.
Currently for every pound private sector workers contribute to their own pension schemes, they also shell out 91p in tax to fund the retirements of those in the public sector, he said.
"We want to tackle this issue now, before we get a few more years down the line and there is a backlash potentially against public sector workers, which a right-wing government - if we ever get such a thing again - could take advantage of," he added.
But Glyn Jenkins, head of pensions at Unison, which represents more than a million public sector workers, said: "It is somewhat ironic that somebody who, as an MP, is a member of one of the world's best final salary pension schemes, tries to play politics by stoking up pensions envy among hard-working families.
"It is a myth that public sector pensions are gold plated. For example, the average local government pension scheme recipient receives just £3,800 per annum, or just £1,600 for female workers."
"Yes they are "gold plated" - as in cheap tatt! Final salary pensions are all well and good but who wants to keep working full time when you are nearing retiremant age. Averaging out your pension based on the past 5-10 years service is surely more fair?" - Karen Murphy, Shropshire
"Is it true all civil servants enjoy a non-contributory pension which has a far greater yield than their NHS counterparts who contribute up to 6% of their salaries?" - Name and address supplied