As part of the package, the government has also awarded a new £5.9bn contract to BAE Systems, a British multinational aerospace, arms and information security company.
The Dreadnought submarine class is the Royal Navy's next-generation nuclear-powered ballistic missile submarine fleet, featuring HMS Dreadnought, HMS Valiant, HMS Warspite, and HMS King George VI. The vessels carry Trident missiles and serve as a key part of the UK's nuclear deterrent.
The ships were built to replace the aging Vanguard-class, which had been in operation since 1992, and maintain the UK's Continuous At Sea Deterrence (CASD).
The Prime Minister said: "Keeping this country safe is the first responsibility of any government - but security isn’t just about what we build, it’s about who builds it. The submarines produced in Barrow protect us all, the jobs and apprenticeships they create change lives."
Despite the announcement, the Prime Minister did not confirm whether he would raise defence spending to 3% of GDP by 2030, a commitment that caused the resignation of John Healey as defence secretary under the previous administration and one that the Burnham government will remain under pressure to outline.