Plans to raise the state pension age to 75 would have "serious financial implications" for older people, a charity has warned.

Age Scotland has urged caution against the proposals by Tory think tank the Centre for Social Justice (CSJ), amid concerns for older people who are unable to work due to ill health.

The move - which is understood to be being considered by the UK Government - would see the pension age rise to 70 by 2028 and 75 by 2035 in a bid to save up to £182 billion.

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In its report, CSJ claims that working longer "has the potential to improve health and wellbeing", however opponents branded the plans "despicable".

Brian Sloan, CEO of Age Scotland said that while he welcomed some of the report, including plans to support older workers, the government should be wary of increasing the pension age.

"We would urge caution at accelerating the increases to state pension age," he said.

"We have already seen the negative impact this has had on the WASPI (Women Against State Pension Increase) women and lessons need to be learnt from this. 

"It is also important to consider that, whilst some older people choose to work past their state pension age, not all are able to do so due to ill health. This would have serious financial implications on older people if they have to wait longer to receive their state pension. 

"Any changes would need to be communicated clearly in order to ensure people are able to plan for their future and are in no way disadvantaged from state pension age increases."

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The pension age in the UK is already set to increase to 67 by 2028 and to 68 by 2046, but the CSJ - co-founded by former Tory leader Iain Duncan-Smith - wants to see a faster increase.

The organisation's report, Ageing Confidently: Supporting an Ageing Workforce, claims that evidence suggests the UK is "not responding to the needs and potential" of an ageing workforce.

It recommended helping older people “access the benefits of work” by giving support to them and employers, such as increased access to flexible working and training opportunities and raising the pension age once this is in place.

However, opposition politicians have hit out at the proposal.

Labour MP Paul Sweeney tweeted: "Life expectancy in the UK is now in decline for the first time since records began in 1982. In Glasgow, average male life expectancy is 73, and 78 for females. 

"What is the Tory plan to address this? Raise the state pension age to 75. They are despicable."

While Ex-pensions minister Ros Altmann said the proposed changes “must not be allowed to happen”.

She tweeted: “Reports of state pension age rising to 75 are shocking. 

“Major changes in pension attitudes required due to big life expectancy differentials. Using age as a strict cut off is not good policy.”

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The CSJ report states: "We propose an increase in the pension age to 75 by 2035.

“While this might seem contrary to a long-standing compassionate attitude to an older generation that have paid their way in the world and deserve to be looked after, we do not believe it should be.

“Working longer has the potential to improve health and wellbeing, increase retirement savings and ensure the full functioning of public services for all.”

A spokesman for the Department of Work and Pensions said: "Everyone’s State Pension age is unique to them and in 2017 we raised the future retirement age to 68 so that it is sustainable now and for future generations. We’re creating opportunities for people of all generations with record employment.”

The report claims one million pension-age Britons want to work but cannot find bosses who will employ them.

It also suggests older staff should be given “mid-life MOTs”, leading to flexible hours and training for those who stay in work.