Airbus has warned it could leave the UK if the country exits the European Union single market and customs union without a transition deal.
The European planemaker said the warning was not part of "project fear, but its "dawning reality".
Airbus employs about 14,000 people at 25 different sites in the UK.
Last week, the outgoing president of the CBI said sections of UK industry faced extinction unless the UK stayed in the EU customs union
It brings together the EU's 28 members in a duty-free area, with a common import tariff for non-EU goods.
Prime Minister Theresa May has ruled out staying in the customs union. The UK is due to leave the EU on 29 March 2019.