Over half a million women have won the right to a full state pension after a Government U-turn.

Stay at home mothers and carers who have not paid enough National Insurance are now eligible.

Ministers will later reveal details on a one-off top-up payment that will allow both men and women to qualify.

But in practice women will make up around 90 per cent of those who will benefit, the Department for Work and Pensions (DWP) said.

Only around a third of women reaching pension age qualify for a full basic state pension of £87 a week.

Under the current system, people can buy back the previous six years of missed NI contributions. But the change means those reaching state pension age between April 5 2008 and April 5 2015 and already have 20 years on their NI record, can buy back six years more.

Mr Purnell said: "The Pensions Bill will transform pension provision and finally bring equality for women and carers so that by 2010 around 75 per cent of women reaching state pension age will be entitled to a full basic state pension, rising to 90 per cent by 2025, compared to around 35 per cent today.

"This is fair, affordable and straightforward and it will give more people the chance of a secure future to look forward to in retirement."

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