The cutting-edge technology would down the unmanned aircraft by targeting their electronic components.
Drone warfare has leapt forward in Ukraine where both sides are using them in large numbers, to strike at short and long distances of more than 900 miles.
China is believed to be developing “drone swarm” attack plans.
So, the West is in a race to build weapons to counter this threat.
One of the challenges is to find a cheap way of taking down drones, given that they are not expensive to mass produce.
The British weapon has an estimated cost of 10p per radio wave shot.
So, it could be a cost-effective alternative to traditional missiles.
The Radio Frequency Directed Energy Weapon (RFDEW) beams radio waves to disrupt or damage the critical electronic components inside drones.
Defence procurement minister James Cartlidge said: “We are already a force to be reckoned with on science and technology, and developments like RFDEW not only make our personnel more lethal and better protected on the battlefield, but also keep the UK a world leader on innovative military kit.
“The war in Ukraine has shown us the importance of deploying uncrewed systems, but we must be able to defend against them too. As we ramp up our defence spending in the coming years, our Defence Drone Strategy will ensure we are at the forefront of this warfighting evolution.”
Ukraine is seeking to build a million drones this year, and Russia is also ramping up production of the unmanned aircraft, as well as receiving large supplies of them from Iran,
The new British weapons system will undergo extensive testing with soldiers over the summer.
It is being developed by a joint team from the Defence Science and Technology Laboratory and Defence Equipment & Support, working with UK industry under Project Hersa.
DSTL chief executive Paul Hollinshead said: “These game-changing systems will deliver decisive operational advantage to the UK armed forces, saving lives and defeating deadly threats.
“World-class capabilities such as this are only possible because of decades of research, expertise and investment in science and technology at DSTL and our partners in UK industry.”
The RFDEW weapon can be used across land, air and sea and has a range of up to one kilometre, which could be extended in the future.
It can be mounted on multiple military vehicles, and uses a mobile power source to produce pulses of a radio frequency energy in a beam that can fire sequenced shots at a single target or be broadened to hit a series of targets.
Facing the threats from China, Russia and other rivals, Rishi Sunak has promised to hike UK defence spending to 2.5 per cent of gross domestic product (GDP) by 2030.
