Contracts potentially worth £32bn were signed last week by three Eurofighter industrial consortia.
The contracts for up to 620 aircraft, plus 90 on option, for the RAF and the German, Italian and Spanish air forces, were signed in Munich by the Eurofighter management agency and the companies providing the airframe and engine.
Defence secretary George Robertson said the contracts will lead to immediate orders worth £1.6bn with British industry.
Initial production contracts include one for production tooling and preparation and for project support. The engine contract is worth around £4.83bn.
The aircraft will be bought in three batches. Subject to a production readiness review in the spring, the aim is to order the first batch of 148 Eurofighters later this year, of which 55 will be for the UK.
In Britain, some 6,000 jobs depend on Eurofighter and this is expected to reach 14,000 at the peak of production. The project will cost Britain £15.9bn on current projections.
Though the Government has promised Eurofighter is ring-fenced against cancellations, cuts to the 232 aircraft Britain is committed to are still possible.