The Government was accused today of making people "work until they drop" under plans to increase the pension age.
The state pension age for men will rise from 65 to 66 at some time from 2016 - nearly a decade earlier than the last government was planning (see the Pensions guide guide).
The exact date of the change has yet to be determined, though the previous government had planned to raise the age from 2024.
Ministers will raise the possibility of extending the pension age to 70 and even older in the following decades to "reinvigorate retirement".
The official age is crucial as it's the point at which the public qualifies for the state pension (see the State Pension Boosting guide).
Unions reacted with anger to the news, accusing the Government of showing its "class bias" just weeks after gaining power.
Paul Kenny, general secretary of the GMB, says: "The Government knows manual workers in the industrial regions of the UK do not enjoy anything like the same life expectancy as professionals or other classes or employees.
"To force someone who has done a lifetime of toil on building sites, farms or in factories to work until they are 66 is completely unacceptable. What on earth are the Liberals doing in this coalition?"
Bob Crow, general secretary of the Rail Maritime and Transport union, says: "As well as hitting pay, living standards, public services and jobs, the latest assault from the Government is work until you drop.
"If you are a rich banker with a private pension you can sail off on your yacht at 55, but for working men and women retirement will be pushed further and further over the horizon in a step back to the days of Dickens.
"That is not sharing the pain, it is hitting the poorest hardest yet again."
Work and Pensions Secretary Iain Duncan Smith will provide more detail on plans to scrap the default retirement age which allows employers to get rid of staff when they reach the age of 65.
He will make the announcement in a speech in London later today, but in an interview with the Daily Telegraph he says: "People are living longer and healthier lives than ever, and the last thing we want is to lose their skills and experience from the workplace due to an arbitrary age limit.
"Now is absolutely the right time to live up to our responsibility to reform our outdated pension system and to take action where the previous government failed to do so."
He adds: "If Britain is to have a stable, affordable pension system, people need to work longer, but we will reward their hard work with a decent state pension that will enable them to enjoy quality of life in their retirement.
"That is why we are issuing a call to evidence on moving the state pension age to 66, and thereafter plan to take a frank look at the relationship between state pension age and life expectancy."
The previous Labour government's policy was to raise the state pension age to 66 in 2024 and then incrementally to 68 by 2046.
Public sector pensions review
Duncan Smith's announcement comes as former Labour Cabinet minister John Hutton embarks on a review of public sector pensions.
As the head of the Independent Pensions Commission, he has been tasked with identifying immediate savings by September and full-scale reforms in time for next year's Budget.
The new Office of Budget Responsibility has suggested the public sector pension bill could more than double to £9 billion a year by 2015.
The National Pensioners Convention also criticised the Government's plans to raise the state pension retirement age, describing it as an attack on the poorest members of society.
The group said the decision ignored important information that showed that life expectancy is linked to affluence.
General secretary Dot Gibson said: "There can be no doubt that the wealthier you are, the longer you live, so raising the retirement age is a direct attack on the very poorest in our society.
"There is a myth that we are all living healthier lives for longer and very little evidence that there are sufficient jobs around for everyone to keep working. This policy isn't about choice, it's about cutting costs and making the poorest pay the highest price.
"We must establish the right to a decent period of retirement otherwise we will soon see people working till they drop."
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