European aircraft giant Airbus Group is buying a majority stake in Bombardier's CSeries program.

The two aircraft manufacturers announced the partnership Monday evening, weeks after the United States announced 300 per cent preliminary duties on exports of the aircraft following a complaint from Airbus rival Boeing.

The CSeries headquarters will remain in the Montreal area but a second assembly line for the 100- to 150-seat plane will be set up at Airbus' facility in Alabama.

The partnership is expected to result in significant CSeries production costs savings by leveraging Airbus' supply chain
expertise.

Airbus will acquire a 50.01 per cent interest in the CSeries Aircraft Limited Partnership (CSALP), which manufactures and sells the plane.

Bombardier will own 31 per cent and the Quebec government's investment agency will hold 19 per cent.