Over 12,000 teachers have written to their MPs to oppose the public sector pensions cuts proposed by Lord Hutton.
In his report last week, Hutton said final salary pensions for public servants were "inherently unfair" and proposed a move towards career average schemes and increased contributions.
The government also wants to link public sector pensions to CPI rather than RPI, a normally higher percentage.
But the National Union of Teachers says the moves pose an unacceptable threat to members of the Teachers' Pension Scheme.
Christine Blower, general secretary of the NUT says the changes proposed by Hutton will lead to a retired teacher on a £10,000 pension being hit by a loss of £35,000 in income over 25 years.
This constitutes a breach of teachers' rights, she says.
"Since 2007, teachers have already been paying more for their pensions and the retirement age has been raised to 65," says Blower.
However pensions experts have spoken out in support of Lord Hutton's key proposals to reform public sector pensions.
These include reducing payouts, increasing contributions and moving away from final salary structures.
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