I assume by neogtiations the unions means, that the government give in to their every demand and members get to keep their pensions as they are, perhaps with a reduced contribution from themselves!
In the private sector we get 5%, if we're lucky, from our employer!
We also have to gamble our investment and hope it grows, you get a guaranteed amount at the end of your working career.
In the public sector you pay just 3.5% and we, the tax payer, pay 19%, how is that in any way, shape or form justifiable.
If you can show me how, without raising taxes or cutting costs elsewhere, or taxing the bankers or taxing the rich (that includes making non-doms pay their taxes), you can pay for the increased costs of your pensions I'm happy to listen.