Pharmaceuticals giant AstraZeneca is to cut 700 jobs in the UK over the next three years and invest £330 million.
The company, which employs 6,700 workers in the UK at eight sites, said it is opening a new research and development centre in Cambridge.
Around 1,600 jobs will be relocated from Alderley Park in Cheshire, with most going to Cambridge.
The firm stressed its long-term commitment to the UK, but the announcement was attacked by trade unions, which complained that high-quality jobs were being lost from the North West.
Pascal Soriot, chief executive officer of AstraZeneca, said: “The changes we are proposing represent an exciting and important opportunity to put science at the heart of everything we do because our long-term success depends on improving R&D productivity and achieving scientific leadership.
“This is a major investment in the future of this company that will enable us to accelerate innovation by improving collaboration, reducing complexity and speeding up decision-making.
“The strategic centres will also allow us to tap into important bioscience hotspots, providing more of our people with easy access to leading-edge academic and industry networks, scientific talent and valuable partnering opportunities.”
Unite national officer Linda McCulloch said: "AstraZeneca's decision to relocate over a thousand jobs to Cambridge is a massive blow for the North West. The company is creating a skills crisis for the local economy.
"After 40 years of success and hundreds of millions of pounds of investment, we are at a loss as to why AstraZeneca is now pulling out of Alderley Park. The region desperately needs this highly-skilled workforce - they make a huge contribution to the economy and to the community.
"Staff will be shell-shocked by this announcement. Skilled scientific jobs are in short supply and there are many families based around Alderley Park with deep roots in the community. It is going to be a real struggle to relocate families hundreds of miles away to Cambridge."
GMB national officer Allan Black said: "This is disastrous news for the UK, and for the North West in particular. The vast majority of the jobs to go are research and development jobs at the Alderley Park site in Cheshire. There has been salami-slicing of jobs at this site but this is by far and away the largest slice of job losses at the site to date.
"These are cutting-edge R&D jobs that are both well-paid and essential for a thriving UK economy.
"Highly-skilled and qualified workers will be put on the scrapheap."