Gordon Brown has been accused of wasting £9bn of public money on his flagship tax credit policy, after official figures showed the Revenue made huge overpayments in the first three years of the scheme.

The latest data, produced by the Office for National Statistics, revealed thattax administrators wrongly handed out £1.7bn to families in 2005-06, bringing to £5.7bn the total amount overpaid since 2003. Much of it will be irrecoverable.