Stone Cloak: UK Shares Drone Jammer Tech with Ukraine

When UK Prime Minister Andy Burnham meets Volodymyr Zelensky at a UK naval base on Monday, he will announce the transfer of intellectual property for a system that has already changed how Ukraine fights. Stone Cloak — a tablet-sized electronic jammer that blocks detection of any drone it is fitted to — is at the heart of this new phase in UK-Ukraine defence cooperation. The Ministry of Defence has already given thousands of these devices to Ukrainian forces.

The announcement marks a shift from supplying finished hardware to enabling local production at scale. Burnham described Stone Cloak as "the best of homegrown British innovation and proven on the frontline."

What Stone Cloak Does

Stone Cloak jammers are designed to block the detection of drones they are fitted to. At the size of a tablet computer, they can be mounted on small attack drones without significantly affecting flight performance. The system works by emitting signals that interfere with Russian air defence radars, preventing them from tracking and targeting the drone.

The UK has already sent thousands of these devices to Ukraine. The decision to share the intellectual property means Ukraine can now manufacture the jammers itself, scaling up production without waiting for shipments from Britain.

From Drone Protection to Cruise Missiles

Downing Street confirmed that following its deployment in Ukraine, Stone Cloak technology will be built into the UK's next generation of long-range weapons. This includes Project Brakestop, a government programme to develop low-cost cruise missiles — self-propelled guided weapons that fly like normal aircraft for much of their flight.

Integrating Stone Cloak into cruise missiles suggests the UK sees electronic warfare as a permanent feature of its future arsenal, not a temporary battlefield adaptation. The lessons from Ukraine are being fed directly into British weapons design.

Burnham's First International Visitor

Zelensky is Burnham's first international visitor since he took office a week ago. No 10 said this "illustrates the strength of the relationship between the two nations." Zelensky was one of the first world leaders Burnham spoke to when he entered Downing Street.

Burnham told the BBC's Laura Kuenssberg that his support for Ukraine was "unwavering — it is 100%." The visit comes less than two weeks after former prime minister Keir Starmer travelled to Kyiv for his final foreign visit.

The two leaders will meet more than 200 Ukrainian military personnel who spent the last three weeks taking part in Exercise Sea Breeze, a 15-country training deployment focused on mine exercises and maritime operations in the Black Sea. The second part of this year's exercise took place in Portland, Dorset, and finished on Friday.

Why Stone Cloak Matters

Drones have become central to the war in Ukraine, used for reconnaissance, artillery spotting, and direct attack. Both sides have invested heavily in electronic warfare to counter them. Stone Cloak gives Ukraine a way to protect its own drones from Russian air defence systems, preserving a critical tactical advantage.

By sharing the intellectual property rather than just shipping finished units, the UK is betting that local production will be faster and more sustainable. It also reduces the logistical burden on British supply chains.

The technology transfer is part of a broader pattern of UK support. Burnham has pledged to maintain Starmer's strong backing for Ukraine, and the Stone Cloak announcement is the first major defence initiative of his premiership.

What Comes Next

Stone Cloak will be built into the UK's next generation of long-range weapons, including Project Brakestop cruise missiles. That means the system will protect not just small drones but larger, more expensive platforms.

For Ukraine, the immediate benefit is the ability to produce Stone Cloak jammers at scale. For the UK, the system represents a template for how to develop and share electronic warfare technology with allies. The frontline testing in Ukraine has already proven the concept works.

Burnham and Zelensky will discuss joint projects including Stone Cloak during Monday's visit. The meeting at the naval base, where Ukrainian personnel have been training alongside British and other allied forces, underscores the operational partnership that underpins the technology transfer.

Stone Cloak is not a silver bullet. No electronic warfare system offers complete protection. But it gives Ukrainian drone operators a better chance of getting their aircraft to the target and back. In a war where drones have become as important as artillery, that margin matters.