French defence giant Thales is teaming up with US aircraft maker Boeing in a bid to secure a flight training deal with the Ministry of Defence (MoD).
Thales won another MoD deal this year for its Watchkeeper plane
The duo have submitted their bid worth up to £10bn (14.7bn euros; $17.9bn) for the MoD's Military Flying Training System (MFTS).
US rivals Lockheed Martin and KBR, an offshoot of oil group Halliburton are also thought to be in the running.
The contract covers an aircrew training for the RAF, Royal Navy and the Army.
"MFTS is a programme that goes to heart of Thales UK's strengths in training and service provision; we know what the customer wants and how to deliver it," said Alex Dorrian, chief executive at Thales UK.
Shares in Thales were marked 0.2 euros, or 0.56%, lower at 35.45 euros.