An Underground line upgrade, part of the now defunct and bitterly opposed private partnership plan (PPP) for the Tube, ended up costing two and a half times more than originally planned, it was announced today.
In 2002, PPP company Tube Lines' cost figure for the Jubilee line upgrade was £285.3 million.
Today, Transport for London (TfL), which has taken over Tube Lines work, said the much-delayed upgrade cost £721 million.
Work had been expected to be finished at the end of 2009 but was finally completed in July this year.
A total of £614 million, or just over 85% of the total, was spent under the PPP arrangements before Tube Lines transferred to TfL in the summer of 2010.
London Underground managing director Mike Brown said today: "The final Jubilee line upgrade cost completely vindicates our decision to end the waste and inefficiency of the PPP and transfer the work to TfL.
"Now we are free of the absurd constraints of the PPP contracts we are able to ensure that future upgrades, including the Northern line, are delivered in a much more efficient and economic way and with far less disruption to Londoners and businesses."