Part of the Airbus factory in Bristol is being sold to engineering giant GKN in a deal worth £136m, it has been announced.
The firm is to acquire the manufacturing operation at the site in Filton, which makes wing components for the Airbus.
The Unite union hailed the deal as "fantastic news" for British manufacturing and said it will help secure the country's aerospace industry for decades.
Airbus has been negotiating to sell Filton to GKN for months, and the two sides have been close to a deal for several weeks.
There was speculation that a deal has been delayed by negotiations over price and a commitment by Airbus to provide the factory with future work on its pending A350 aircraft.
The factory was put up for sale by Airbus's parent, EADS, as part of its Power 8 restructuring programme.
GKN chief executive Sir Kevin Smith said: "The acquisition of the Filton wing components and assemblies manufacturing operation is a further exciting step in the development of GKN's aerospace business.
"The strategic logic is compelling. It brings a long-term partnership with Airbus and a strong order backlog which supports solid growth.
"In addition, the position secured on A350 XWB provides future growth at the leading edge of aerospace composites manufacturing technology.
"Filton is already a centre of excellence in metallic structures for Airbus and we intend to invest in the operation so that it also becomes a centre of excellence in composite wing structures serving the global aerospace market."