Rolls-Royce has signed a £1bn contract with the Ministry of Defence (MoD) to keep Royal Navy submarines at sea for the next 10 years.
Seventy jobs were cut at the firm's submarine division in 2006
The Derby-based company will supply and maintain nuclear powerplant systems on board the current and future fleets of submarines as part of the deal.
It covers the 13 Swiftsure, Trafalgar and Vanguard models along with the new Astute class submarines.
The contract will secure jobs at the firm's production site at Raynesway.
Lord Drayson, Minister of State for Defence Equipment and Support, said: "This landmark partnering contract ensures the United Kingdom secures its ability to manufacture and support this strategic equipment in the future.
"It will deliver more cost-effective management of submarine maintenance and safeguard jobs and essential skills in the UK."
Steve Ludlam, Rolls-Royce President Submarines, added: "The long-term nature of the agreement allows both sides to better plan and prioritise, sharing the benefits of savings made."
Seventy jobs were cut at the company's submarine division in Derby in January 2006.