A joint deal has been signed to maintain progress on a global air programme which is vital to Lancashire's aerospace industry.

Britain, Italy and Japan are backing the under-development Tempest aircraft, the future fighter which is expected to replace the Typhoon in the 2030s.

Design work on Tempest has heavily involved experts at BAE's Samlesbury and Warton plants and the three nations have now signed a convention on establishing the 'Global Combat Air Programme' to agree upon the shared design and delivery of the next generation aircraft.

Last September the partners had already settled on a collaboration agreement to support long-term working arrangements to advance the Tempest programme, which safeguards hundreds of hi-tech county jobs.

The international partnership has now been up and running for 12 months and the convention is seen as an important milestone as the concept aircraft matures.

Further talks are ongoing between BAE, Leonardo and Mitsubishi Heavy Industries, on the industrial scope of Tempest, the most recent taking place in Tokyo.

Herman Claesen, managing director, Future Combat Air Systems, for BAE's air sector, said: "We welcome the agreement signed by the governments of Italy, Japan and the UK, and the continued progress with our industrial partners to advance the future joint business construct that will enable us to deliver the next generation combat aircraft.

"We’re proud to represent the UK on this exciting and forward-leaning partnership, which will deliver a crucial and affordable defence capability and help to maintain our sovereign combat air skills in the UK.”

Guglielmo Maviglia, Leonardo's GCAP programme director, said: "We welcome the announcement made by our governments and we are proud to be part of the GCAP programme along with our partners.

"GCAP, which will see the development of an innovative next generation core platform underpinned by advanced technology, is charting a transformational new approach to international industrial collaboration.

"Through its ambition, the programme will maintain the competitiveness of our industries at an international level."

Hitoshi Shiraishi, senior fellow, GCAP, Mitsubishi Heavy Industries, added: "We would like to very much welcome the signing of the treaty by the governments of Italy, the UK and Japan.

"In addition, following the conclusion of this treaty, we would like to work even more closely with our partners in Italy and the UK to promote GCAP. We will also work to ensure that GCAP contributes to strengthening Japan’s defence capabilities.”

It has been confirmed the HQ for GCAP will be in the UK with a Japanese chief exec. The first business construct will also be in the UK, with an Italian leader.

An estimated 9,000 people are working on GCAP worldwide, with more than 1,000 suppliers involved across the partner nations.