Up to 158 jobs are to go at an armoured fighting vehicle plant after the government's latest defence review.
The US firm Lockheed Martin said its workforce at Ampthill, Bedfordshire, would be cut by about a sixth.
It was a "direct result" of the government's termination of the Warrior Capability Sustainment Programme, it said.
The site, part of its missiles and fire control business, currently employs about 900 people.
Lockheed Martin said its Warrior armoured vehicles were first produced 30 years ago and its site at Ampthill repurposes them for the Army - mainly by upgrading its turret.
The company said the Warrior contract was "a major programme for the site" and its termination would mean job losses affecting "both direct and indirect employees".
Lee Fellows, vice president and general manager at the site, said: "Despite the need for this workforce reduction, we remain a strong business.
"This exercise will ensure that we maintain competitiveness by delivering affordable products and services to customers while positioning for future growth opportunities that will benefit the facility in the longer term."
It will support "impacted employees" and provide them with assistance, he added.
Work to support the Ajax armoured vehicle programme and programmes in the classified special projects and mission support areas of the business remained unaffected, the company said.
A Ministry of Defence spokeswoman said: "The MOD greatly values the partnership with Lockheed Martin and has spent over £1bn over the last four years with the company including F-35 Lightning, the Ajax turret and flight training programmes.
"We look forward to working with the company on any future procurements."