Industrialist and former Babcock chairman Sir John Parker was tasked with delivering an independent report following the Budget in March, which announced the government’s desire to deliver a strategy for the naval sector.

“It is evident that Sir John has delivered his report, and the government is now obliged to publish it,” said Prospect’s head of research, Jonathan Green.

“Sitting on it is unacceptable and raises questions about government transparency. A national shipbuilding strategy is vital to workforce planning, maintaining skills and delivering the defence capabilities the UK needs.

“The government had appeared to be moving in the right direction in terms of joined-up thinking on defence with the announcement of a consultation on defence industrial policy. However, this delayed publication seems like a retrograde step.

“The Commons’ defence select committee has just raised some very important concerns about the state of UK shipbuilding and the need for apprenticeship targets in key skill areas. We need to see that these concerns are being addressed with a coherent shipbuilding strategy.”

Prospect has 11,000 members working in defence across the public and private sectors.