THE defence secretary has reinforced his promise to back Barrow's shipyard with a nuclear deterrent 'triple lock'.

John Healey has committed to building four nuclear submarines - which support jobs at the shipyard - as well as maintaining the continuous at-sea deterrent and providing repairs.

He made the comments after he boarded a Barrow-built Vanguard submarine at the Navy's Clyde base in Scotland for the final leg of its return journey home after completing the UK’s latest patrol.  

Officials say the Government’s commitment to security is clear with a Strategic Defence Review already underway that will determine the roles, capabilities and reforms required by UK Defence to meet the challenges, threats and opportunities of the 21st Century.

Mr Healey said: "Royal Navy submariners make extraordinary sacrifices to keep us all safe and it was an honour to thank the crew on behalf of the British people. As they return home, we salute their courage, dedication, and professionalism. 

"Our new Government is unwavering in our commitment to our nuclear deterrent, maintained on behalf of the UK and our NATO allies.

"Our ‘triple-lock’ will safeguard Britain for generations to come."

During his visit to the 15,000-tonne vessel, Mr Healey thanked the crew of 140 Royal Navy submariners for their dedicated service and wished them well as they prepared to reunite with their families. 

He was also given an operational briefing and toured the submarine, which is armed with the UK’s Trident nuclear missiles.

Joining the Defence Secretary in thanking the returning submariners was First Sea Lord, Admiral Sir Ben Key; Director Submarines, Rear Admiral Andy Perks; Commodore of the Submarine Flotilla, Commodore Paul Dunn; and Naval Base Commander Clyde, Commodore Sharon Malkin.  

The name of the vessel, length of patrol, and its location at sea are all closely guarded secrets.

On board, only a select few are authorised to know where in the ocean depths they are operating, with the rest of the crew dutifully carrying out their roles unaware of their location. 

A new class of ballistic submarine – the Dreadnought Class – is currently under construction at Barrow and is expected to replace the Vanguard submarines by the 2030s.

More than 40,000 UK jobs are supported through defence nuclear work.