Trade union Unite has rejected the government's latest proposal for reform of the NHS pension scheme (NHSPS).
In December, most of the major trade unions including Unite signed a "heads of agreement" document on pension reform to take back to their executive bodies for approval.
Unite's health sector national industrial committee has rejected the agreement, claiming its grounds are unfair.
Public sector workers are facing various reforms to their pensions which, depending on which scheme they belong to, could include later retirement dates, increased contribution rates and a move from final salary to career average accrual arrangements.
The December agreement proposed the new NHSPS would have an accrual rate of 1/54th of earnings each year, with the average member contribution set at 9.8%.
Staff earning less than £26,557 protected from contribution increases for 2012, whilst those earning more would pay increases of up to 2.4% in 2012.
However, Unite objected to these proposals because it claimed a large proportion of NHS staff will see their contributions jump from 6.5% to 9.3% by 2014/15, whilst some will see contributions increase by almost 50% to 14.5% of their salaries.
The union also said the move to career average instead of final salary arrangements will have an adverse effect on female staff who are more likely to have taken career breaks to care for children.
Unite objected to the increase of the pension age to fall in line with the state pension age, which will reach 66 by 2020, as it said this could see some workers over the age of 60 forced to continue doing physical tasks such as heavy lifting.
Len McCluskey, general secretary of Unite, said: "The government's attacks on public sector pensions are politically motivated, as part of an overall design to privatise the NHS, cut public services, break-up the national pay agreements, and disrupt legitimate trade union activities and organisation.
"Unite believes it is important to continue a campaign to maintain a fair and equitable system of public sector pensions and calls on ministers to enter into real, genuine and meaningful negotiations on the future of NHS pensions and public sector pensions."
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