A radical shake-up of state pensions will leave up to half of pensioners worse off by 2060, it has been revealed.

High earners and recent immigrants will be among those hit by the government's plans to reform the pensions system.

Ministers said their proposals would simplify the current complicated system and particularly benefit women, low earners and the self-employed, with a single flat rate state pension, equivalent to around £144 a week in today's money, introduced for new pensioners from 2017.

But the Government's White Paper revealed that a number of people will lose out.

Under the new system, around one in five people reaching state pension age after 2017 will be better off, less than one in 10 will be worse off and the others will see no difference.

But the proportion who will be worse off will rise rapidly, with more than half of people reaching state pension age after 2060 left worse off. The majority of these will be worse off by more than £2.

The respected Institute for Fiscal Studies said the proposals implied a cut in pension entitlements for most people in the long run.

Pensions Minister Steve Webb said high earners would be among those whose pensions would be affected, adding there were "far more winners".

Anyone recently arrived in this country who isn't able to build up 10 years' worth of National Insurance contributions before state retirement age will not get a state pension.

Mr Webb said millions of people needed means-tested top-ups under the current system, adding: "Our simple, single tier pension will provide a decent, solid foundation for new pensioners in an otherwise less certain world."