Universal credit £40m write-off
9 December 2013 Last updated at 22:28 GMT
More than £40m has been written off on software and computing costs in implementing the new universal credit system.
But Work and Pensions Secretary Iain Duncan Smith has rejected claims that his flagship welfare policy is a "debacle".
He was being questioned by MPs amid fears the universal credit system will miss key targets and concerns over the IT system being used.
Carole Walker reports.