BAE Systems has announced a contract valued at £5 billion to supply aircraft to Qatar, helping to secure jobs in the UK.
The deal to supply Typhoon aircraft to the Qatar Emiri Air Force includes a support and training package.
The contract is subject to financing conditions and receipt by the company of first payment, expected to be fulfilled no later than mid-2018.
The contract provides for 24 Typhoon aircraft with delivery expected to commence in late 2022.
Around 5,000 workers in the UK are employed on building the Typhoon, mainly at Warton in Lancashire.
BAE Systems is the prime contractor for both the provision of the aircraft and the agreed arrangements for the in-service support and initial training.
Defence Secretary Gavin Williamson oversaw the signing of the deal with his Qatari counterpart, Khalid bin Mohammed al Attiyah.
It is said to be the biggest export deal for the Typhoon in a decade.
The contract will secure work on the production line at Warton into the next decade.
The Defence Secretary also agreed a package of training and co-operation between the air forces which will see them working together more regularly, including Qatari pilots and ground crew training in the UK.
Qatar is the ninth country to buy the Typhoon, with this year seeing the first delivered to Oman.