£3.4bn spent ‘improving’ 22 miles of road

The cost of widening the M25 motorway has increased by a quarter because of failings by the Highways Agency, a government report has said.

The project covers 22 miles (35km) between junction 16 and junction 23.

But an 18-month delay meant the contract was let in May 2009 at the height of the credit crisis, a National Audit Office (NAO) report said.

This increased the cost by £660m to £3.4bn, the report said.