The Ministry of Defence (MOD) has signed a £250m contract starting the next phase of developing Tempest - the UK's future sixth-generation fighter jet.
The contract, signed with BAE Systems, marks the formal start of the project's Concept and Assessment phase, which will see investment in the digital and physical infrastructure.
This will see Tempest built from a 'digital first' footing, allowing simulated design and testing.
The contract will also define and design the future combat air system, mature technologies across the system, invest in the workforce and enable major programme choices by 2024.
The Defence Secretary announced the contract at BAE Systems' site in Warton, Lancashire - the centre of development for the programme.
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Ben Wallace said the contract marked "a momentous step in the next phase" of the Tempest programme.
He added it will boost the UK's "already world-leading air industry" and make sure "the UK remains at the top table when it comes to combat air".
The investment is part of over £2 billion of Government spending on Tempest across the next four years - as announced in the Defence Command Paper.
The programme is expected to combine a core aircraft with a number of capabilities, such as an uncrewed aircraft and advanced data systems, to form a next-generation mix designed to enter service from the mid-2030s.
Richard Berthon, UK Director of Future Combat Air, said the project is "hugely important" in making sure the UK and its allies have a "battle-winning edge for the future".
"Developing the system allows us to drive a revolution in digital development and harness the power of open systems architecture," he said.
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However, in the Infrastructure and Projects Authority (IPA) annual report 2021, the project was given an 'amber/red' status.
This means the "successful delivery of the project is in doubt, with major risks or issues apparent in a number of key areas" and "urgent action" is required.
The report also said that whilst a review of the project's timeline to the next phase will not hinder the Concept and Assessment phase, it "significantly increases" the programme's risk in the next phase.
It also stated "further pressure through Annual Budgeting Cycle 21 on the 10-year profile increases the risk to Initial Operating Capability".
The programme to design a future combat air system is a major international effort, with the UK delivering the jet with international partners.
Last year, the UK, Italy and Sweden signed a Memorandum of Understanding to collaborate on the project, although the Government says it is "too early to say" where parts of the Tempest fighter jet will be built.
During his visit to Tokyo last week, Mr Wallace and Japanese Defence Minister Nobuo Kishi agreed to speed up discussions between the UK and Japan on developing sub-systems for Tempest.
Cover image: Tempest combat aircraft (Picture: MOD).