Cyber terrorists are constantly trying cripple Britain's defences, Royal Navy admiral warns

Vice Admiral Jerry Kyd said every aspect of UK life was being targeted by hostile states wanting to ‘do us harm’.

The 52-year-old naval officer’s comments come as concerns over the ability of the UK’s new supersonic F-35 stealth jet to defend against cyber attacks resurfaced.

The multi-billion pound weapons platform is the most advanced warplane ever built and will be critical to Britain’s future defence, with the UK having already spent £6.2bn on two new aircraft carriers purpose-built to operate them.

However, officials from a US government watchdog warned earlier this year the fighter-jet was woefully under-prepared to defend against malware and other cyber attacks.

Vice Adm Kyd, former captain of HMS Queen Elizabeth who is now the Royal Navy’s fleet commander, insisted the F-35’s systems were ‘as protected as we need them to be’.

But he said: ‘Nothing is absolutely 100 per cent cast-iron. You’re a fool if you think you don’t have to work hard at defending against your vulnerabilities. We take this extremely seriously.

‘We undergo attack everyday across not just the defence sector but across all parts of business, so we should never let up our guard.

‘What I can say is the F-35 and the carriers are as protected as we need them to be to ensure capability (is protected).

‘But we must never relax. It’s like a cheetah-gazelle race or fight in the cyber world against state actors and non state actors, many of whom are malign and want to do us harm.’

Vice Adm Kyd insisted the ‘character of warfare was changing’ rapidly, branching out from traditional ‘heavy metal’ like ships and tanks and into the ‘cyber frontier and space frontier’.

He said it was critical Britain continued to do everything it can to stay ahead of its enemies and blaze a trail in the digital war zones of the future.

‘The cyber world is a brave new frontier of warfare,’ he told The News. ‘The digital space needs to be dominated, controlled and understood because my word, our potential foes are doing that at pace.’

HMS Queen Elizabeth and her sister ship, HMS Prince of Wales, are to be the cornerstone of naval defence for the next 50 years.

The £3.1bn-a-piece vessels are the only ones purpose-built to operate ‘5th generation’ fighter jets like the Lockheed Martin F-35B.

However, Vice Adm Kyd said Queen Elizabeth could soon be joined by a fleet of unmanned vehicles to fight the wars of the future.

He said: ‘I do see great changes coming up in the future.

‘Within 10 years I think we will find the flight deck full of unmanned aerial vehicles doing air-to-air refuelling and reconnaissance and even carrying weaponry.

‘I think that’s happening really fast.’

Queen Elizabeth is currently more than 100 miles off the east coast of Florida carrying out her second phase of tests with the F-35.

She is due to return to Portsmouth before Christmas, with her maiden deployment earmarked for 2021.