The number of people in Britain working beyond the age of 65 is rising fast, official figures indicate, as thousands of pensioners attempt to boost their income in retirement.

In the last three months, 40000 people over the age of 65 have joined the work force, taking the total b umber to 823000.

This mean that one in 12 people over the age of 65 are now working the highest number since the office for national statistics started keeping such figures in 1992.

The figures suggest that thousands of pensioners are going back to fund their slim incomes, or that they lack the financial security to retire in the first place, according to experts. Some are also actively choosing to work longer, while others are doing so to help support their children or grandchildren.

The latest date demonstrates how the recession has changed the face of Britain's workforce, leading to far more part-time workers and older workers, while leaving many young people out of work for more than two years.

Last month, the government proposed scrapping the default retirement age to keep people in the workforce longer to ease the pension crisis. It is also suggested that the retirement age be rised to 66 far sooner than proposed.

The current ration for four working adults for every pensioner will fall to three within a decade and two by 2040

Mr Latif Khalaf, pension analyst at Hargreacesl Lansdown the independent financial advisers, said "most of us want to retire as soon as possible, but many people find they just cannot afford to, the state pension is just to measly and private pensions aren't adequate enough to cover the shortfall".

Part of the reason for the small private pensions has been falling annuity rate, the figures use to calculate most pensions, in the wake of emergency measures to prop up the economy during the financial crisis.

The trend for more older people working the number of people over age of 65 working has doubled in less than a decade is also said to be a reflection of their better health and desire by some to stay active./

The figures were published as part of the statistic office monthly update on unemployment, which indicated the number of people in work had jumped by far more than most economists had expected.