The latest phase of the upgrade to Rolls-Royce's Raynesway factory in Derby will officially open later today.
The firm secured a £1 billion contract from the Ministry of Defence in June to build reactors for the next generation of nuclear submarines.
Atlantic House will be officially opened by HRH the Duke of Kent.
More top news
A man from Chesterton in Staffordshire has been jailed for life for murdering a woman at his home.
A mum was left disgusted after biting into a "rat's tail" lodged in a Tesco's Finest teacake.
A dry and fine day. Some thundery rain possible later.