COMPLETION of a Barrow-built submarine took more than two years longer than planned, according to a report, amid concern over major defence projects in Britain.

A review by the National Audit Office (NAO) revealed that just eight major Ministry of Defence (MoD) programmes had between them racked up combined delays of more than 20 years.

The report said the fifth Barrow-built Astute attack submarine was delayed by 25 months, with a 'significant' increase in costs since the start of the contract.

Boat five, named Anson, launched from Barrow in April.

The public spending watchdog’s examination of 20 key projects, which had a combined budget of £120 billion highlighted 'recurring underlying causes of persistent delays and cost increases'.

The report said BAE Systems is 'carrying out specific interventions to improve contract delivery'.

"Delays in delivery of the fifth boat in the programme are primarily a consequence of issues with earlier boats in the programme, particularly Boat 4," the report said.

"The department’s delivery team is monitoring a quality improvement plan being implemented by the supplier.

"In early 2020, the parties agreed a contract amendment to offset supplier claims and changes to user requirements. Covid-19 will increase schedule slippage."

Gareth Davies, the head of the NAO, said: “Too often, the MoD doesn’t deliver its major equipment contracts as planned due to a combination of supplier underperformance, a failure of the MoD and suppliers to get to grips with the technical complexity of projects, and short-term solutions to affordability problems.

“To ensure defence contracts deliver value to taxpayers, the MoD must follow through on its efforts to embed good practice in its relationship with suppliers."

An MoD spokesman said: “We are responsible for delivering a huge range of complex equipment programmes. Aided by our £24bn spending settlement, we remain committed to delivering value for money through new streamlined processes and developing our industry contracts with a focus on delivery.”