The Department for Transport has been praised for keeping infrastructure costs for the Thameslink Programme to budget but also warned about the impact delays in the procurement of rolling stock could have on the project.
A report by the National Audit Office has shown that although phase one of the programme came in £143 million under budget at £1.704 billion, problems finalising the £1.6 billion rolling stock contract still threatened its future.
Siemens was announced as the preferred train builder in 2011 but ministers are yet to sign off the order.
The National Audit Office has said the delay questions whether the DfT will be able to deliver the programme by 2018 and to the £6 billion budget.
Amyas Morse, head of the National Audit Office, said: “It’s too early in the Thameslink programme to conclude on whether or not it will achieve value for money. That will have to wait until the new service is running. However, there has been good progress in delivering the first stage of the infrastructure part of the programme on time and under budget, which the Department now needs to build on.
“Our principal concern is around the delay in agreeing the contract to build new trains which raises questions about the feasibility of delivering the whole programme by 2018.”
The programme’s focus is currently on London Bridge station where platforms 14, 15 and 16 have been closed off to allow redevelopment work to start.