Over 30 of the government's flagship projects are at serious risk of failure with some classed as unachievable, Whitehall documents have revealed.
High-profile schemes including High Speed 2, the benefit cap, a pilot scheme introducing payment by results for companies aiming to reform offenders and broadband roll-out, have all had warnings raised against them.
Francis Maude, Minister for the Cabinet Office, said: "Major projects need scrutiny and support if we are to succeed in the global race. Publishing this report will transform the management of expensive, important projects and will help hold Whitehall to account.
"I was staggered when I came into Government and found a relaxed approach to managing projects worth hundreds of billions of pounds.
"Problems were swept under the carpet where they festered at the taxpayers' expense. In many places the Civil Service lacked project management skills and had a lamentable record of project delivery."