THERESA May has hailed a shipbuilding contract worth up to £20 billion between BAE Systems and the Australian Government as the biggest naval defence contract for a decade.

She suggested this was a “perfect illustration” of Global Britain, clinching a lucrative deal as the country embarked on life beyond the European Union.

BAE Systems has been chosen as the preferred bidder for the SEA 5000 Future Frigate, beating off competition from Italy and Spain.

The UK company will build nine warships in Adelaide with a design based on Britain’s Type 26 Global Combat Ship; the first export of a British design for new-build frigates since the 1970s.

No 10 explained the agreement would secure more than 4000 jobs in Australia and also boost Britain’s export economy for generations to come.

In turn, it said it was hoped that the contract would also benefit the UK economy with exports having the potential to drive regional growth, create new jobs and showcase the strength of British innovation on the world stage.

The multi-billion pound deal is the result of four years of intensive Government engagement involving a number of departments across Whitehall.

The Prime Minister has been directly involved in making the case for the UK bid, including in bilateral talks with her Australian counterpart Malcolm Turnbull at Chequers earlier this year.

Over the past 18 months Boris Johnson, the Foreign Secretary, Gavin Williamson, the Defence Secretary, and Liam Fox, the International Trade Secretary, have all visited Australia to extol the benefits of Britain’s world-class design, engineering and innovation.

“The sheer scale and nature of this contract puts the UK at the very forefront of maritime design and engineering and demonstrates what can be achieved by UK industry and Government working hand-in-hand,” declared Mrs May.

“We have always been clear that as we leave the EU we have an opportunity to build on our close relationships with allies like Australia. This deal is a perfect illustration that the Government is doing exactly that.

“And while this is an enormous boost for the UK economy, it will also cement our strategic partnership with one of our oldest and closest friends for decades to come,” she added.

Dr Fox pointed out how the UK and Australia already enjoyed a strong trading relationship worth more than £13 billion a year.

“Today’s announcement is a further boost to this relationship, which will create significant opportunities for companies in both countries to deepen their trading ties.”

These opportunities, the International Trade Secretary explained, included increased data and information sharing, high-end technology transfer, and collaboration at the cutting-edge of maritime expertise.

Downing Street also pointed out how the new contract would build on the century-long ties between the two nations and would allow “interoperability between Australian and Royal Navy ships amid a climate of intensifying threats around the world, especially in the Middle East and the Asia-Pacific regions”.

The 6,900 tonne multi-mission warships are designed to support anti-submarine warfare and a whole range of other operations anywhere in the world. They will form a key part of Australia’s hugely respected Navy.

The contract was secured with the UK committed to getting eight of the Type 26 warfare frigates, which are currently in-build on the River Clyde and are set to enter service with the Royal Navy in the 2020s.

Charles Woodburn for BAE Systems added: “I am proud that our world class anti-submarine warfare design and our approach to transferring technology and skills to the nations in which we work is expected to contribute to the development of an enduring world-class naval shipbuilding industry in Australia.”