9,000 jobs have been secured after the government announced a £15 billion investment in its nuclear warhead programme.
It said it would be adding to the UK's defence systems, with upgrades coming to the Atomic Weapons Establishment (AWE) in Aldermaston including 12 new attack submarines.
The move comes as the Government publishes the outcome of its Strategic Defence Review, to "protect the UK's national security against a backdrop of increasing geopolitical threats".
Secretary of state for defence John Healey said that he celebrated the "essential and unique work" done by AWE.
In a statement, AWE said "The UK Defence Spending Review, announced by the Prime Minister, outlines significant investment in nuclear security, including the modernisation of infrastructure at AWE.
"AWE's nuclear warhead programme features some of the most advanced and sensitive science, engineering and manufacturing facilities in the UK."
The Prime Minister said the world had changed and there was greater instability and the UK needed to respond to those threats.
He added: "We have seen what's happened in Ukraine… Russia has shown in recent weeks it is not serious about peace and we have to be ready."
The Labour MP for Aldermaston, Olivia Bailey, said that the £15bn investment will be "crucial for national security" and "transformational for Reading West and Mid Berkshire".
"The investment will include billions for the modernisation of infrastructure at the Aldermaston site … in addition to thousands of jobs in the defence supply chain in Reading West and Mid Berkshire and across the UK", she said.
Ms Bailey said: "I am proud to represent a constituency that is so vital to this country's national security, with thousands of people working in the defence sector to keep us safe.
"This is a significant investment in this country's national security and reinforces my constituencies' place at the very forefront of the UK defence sector."