Royal Navy could be forced to spend 'tens of millions' to turn patrol ships into frigates amid fears over Type 31 plans

The engineering firm was last week named preferred bidder to build the five Type 31 warships, which will replace the five general purpose Type 23 frigates.

Each costing £250m – around a quarter of the cost per ship of the larger and more advanced Type 26 frigates – they will be built in Scotland and are expected to be based in Portsmouth.

Naval top brass have demanded the first of the new warships is ready for service in 2023 – when the first Type 23 is due to retire from the fleet.

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However, defence sources claimed this will be a ‘challenging, if not impossible’ deadline for Babcock and its industry consortium allies to meet.

A source said: ‘I don’t think there’s a big ship manufacturer in the world that could deliver this in four years.’

Now insiders have warned at least one of the new batch of second generation River-class offshore patrol vessels (OPV) would need to be upgraded to act as a temporary frigate and meet the government’s pledge to maintain a fleet of 19 frigates and destroyers.

The overhaul could see improvements to weapons systems with more sophisticated sensors also being added.

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‘No-one has come up with a solution for extending the Type 23s and they’re now running out of time to solve this,’ an industry insider added.

The Ministry of Defence (MoD) told The News it has not formulated any contingency plans if the Type 31 project can’t meet its deadline, saying such school of thought was not necessary until the design and build phase was launched.

However, Admiral Lord Alan West, former First Sea Lord, was worried by the situation. He said: ‘I’m all for increasing the armament of the OPV but it doesn’t make up for having more frigates.

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‘I can’t see anyway that they will be able to build the Type 31e in time before the first of the Type 23s is retired. That’s a real worry.’

The MoD insisted it was down to Babcock to propose build strategies that will meet the project’s deadline, with a spokesman adding: ‘We have stated that we want the first Type 31 ship in the water by 2023.’

Babcock declined to comment about the concerns over the project’s build schedule.

However, the company insisted work would begin immediately following formal contract award later this financial year, with ‘detailed design work to start now and manufacture commencing in 2021 and concluding in 2027’.

The Type 31 is based off the Arrowhead 140 warship design. The programme will support more than 2,500 jobs across the UK, with different elements of the frigates being assembled and built at British shipyards.