Mr Healey will use the visit to highlight the government’s “triple-lock” on the nuclear deterrent, which includes building four new nuclear submarines in Barrow-in-Furness in Cumbria, maintaining the UK’s continuous at sea nuclear deterrent and delivering all future upgrades needed.

He said: “This investment in Britain’s defence will deliver a long-term boost to British business, jobs and national security.

“In line with our Plan for Change, external, this deal with Rolls-Royce, a historic British success story, will support high-skilled UK jobs, who equip the thousands of submariners that keep us all safe.

“We are showing defence can be an engine for growth, while also driving better value for taxpayer money.”

Steve Carlier, president of Rolls-Royce Submarines, said: “We’re delighted to announce the Unity contract, which confirms our commitment to the Royal Navy and the Defence Nuclear Enterprise.

“This long-term contract enables us to invest in the right skills, equipment and facilities to play our part in protecting UK interests at home and overseas.”

Rolls-Royce Submarines is already doubling the size of its Raynesway site and has recently started moving into specially built warehouses in Pride Park.