Labour and a growing proportion of Liberal Democrat MPs plan to mount an assault on the acceleration of the state pension age (SPA), Rachel Reeves, shadow pensions minister says.
In a private members' debate on Wednesday, MPs grilled pensions minister Steve Webb on the clause in the Pensions Bill.
MPs called on Webb to reconsider plans to raise the SPA to 66 by 2020 for everyone, meaning some women in their fifties will face a wait of an extra two years before they can claim.
"Labour recognises the longevity rise, and we accept acceleration, but not before 2020," Reeves said after the debate.
"There are too many changes already. As a compromise, we propose raising the SPA to 66 by 2022, saving the government £20bn rather than £30bn."
Reeves said the policy is unpopular amongst Liberal Democrats and hinted at a rebellion at the second reading of the Pensions Bill, which is expected to be in early June.
"The second reading of the Pensions Bill is due very soon and we are hoping to mobilise as much support as possible against the clause on SPA," she said.
"Two Lib Dems spoke against the changes today because those changes were not in the coalition agreement. The government could not find a single Lib Dem MP to speak in favour of the changes today [apart from the minister]."
So far one in five Liberal Democrat MPs have signed an early day motion (EDM) calling on the government to reconsider its state pension reforms.
To date 140 MPs have signed the EDM, with two more having signed yesterday after the debate.
The majority of signatures are Labour but all major parties including the Conservatives are represented in the motion.
Reeves said hundreds of people are writing to their MPs urging them to sign the EDM, and 10,000 people have signed a Unions Together petition against the SPA policy.
Age UK will lobby Parliament on Wednesday 18 May and present the petition to the minister.
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