Originally published in the Daily Telegraph. Clive Higgins, Charles Woodburn, Chris Allam and Adam Riddle.

The Prime Minister said earlier this week that we are living in a world that feels more dangerous than it has since the end of the Cold War. He and other world leaders are recognising that governments need to do more to protect national security and keep citizens safe and are therefore increasing their defence spending.

Here in the UK, we have the national industrial capabilities to develop, produce and sustain vital defence assets across every domain of warfare. In particular, we are one of only a small number of nations that have advanced sovereign combat air capability thanks to our long history of research and development in the sector.

This vital national asset gives Britain a significant strategic advantage, ensuring the UK can contribute to regional and global security, deter aggression, project our national authority and protect UK interests both at home and internationally.

We welcome the Prime Minister's announcement to radically reform defence procurement and boost investment in the UK's defence industrial base. However, we hear arguments from some quarters that the UK Government should shift to buying more off the shelf military equipment from overseas.

This completely overlooks the strategic need for the UK to retain control over our own security, which has never been more crucial than it is in today's challenging geopolitical landscape. Without that sovereignty, the UK would become ever more reliant on other nations, whose support can't always be taken for granted. The UK's combat air sector has consistently delivered cutting-edge capabilities, like the Tornado and Typhoon, to the UK and our allies through international partnerships. Remaining a global leader requires an enduring commitment. RAF Typhoons play a key role in defending the skies above the UK, Europe and the Middle East today, because government and industry made significant investments in our sovereign capabilities and the sustainment of skills decades ago.

The programme generates around £1.6bn annually to the UK economy and, thanks to its export success, has already returned more than double the UK Government's initial investment, helping to contribute to our broader economic prosperity.

In 2024, we employ more than 20,000 people across our businesses in the combat air sector, with around 50,000 highly skilled jobs in total across the supply chains in every part of the UK. This number includes hundreds of dedicated industry engineers and technicians stationed at RAF bases, working alongside serving military personnel, to ensure that the RAF's fighter jets are ready to deploy anywhere in the world at a moment's notice.

But in a world of finite resources and rapidly evolving threats, we need to deliver equipment more quickly and cost effectively to our armed forces.

The UK Government's Combat Air Strategy gave our industry the confidence to make significant investments to develop new technologies and radically transform the way we design and build combat aircraft. But it is essential that the strategy is implemented in full if we are to secure the UK's combat air sector for the future.

As leaders of the sovereign combat air industrial base, BAE Systems, Leonardo UK, MBDA and Rolls-Royce are working together with the UK Ministry of Defence to deliver Tempest, the UK's sixth generation fighter jet in half the time and at significantly less cost than other previous programmes.

We know how important it is to meet the challenges of industrial innovation head-on. That's why we're building on our existing expertise to bring together the best minds from across the sector and beyond.

We now have more than 3,500 people working on the programme, supported by around 600 other organisations including many SMEs and leading UK universities.

And we're working with Italy and Japan under the Global Combat Air Programme (GCAP) to design and develop this next generation aircraft. Tempest demands the creation of novel cutting-edge technologies and capabilities to maintain air superiority and address threats in future combat environments.

Pooling our expertise and sharing development costs will enable the UK and our allies to stay ahead of future threats, while delivering significant economic benefits right here at home.

The GCAP programme is estimated to contribute £37bn to the UK economy through to 2070, 85pc of which will be felt outside of London and the South East.

It will also enable significant export potential of home-grown, world leading defence technology, delivering a further boost to the UK economy.

The need to retain control over our own security is clear, as is the long-term economic benefit.

Staying committed to the UK's combat air sector is essential to ensure that the UK Government and our Armed Forces can keep our nation safe and protect the freedom we should never take for granted.

Clive Higgins is chairman and chief executive of Leonardo UK; Charles Woodburn is chief executive of BAE Systems; Chris Allam is managing director of MBDA UK; Adam Riddle is president for defence at Rolls-Royce.