Environmental activists from the group Heathrow Pause have warned they are planning to operate small drones around Heathrow next month in an effort to ground flights.

The group, an offshoot of the wider Extinction Rebellion climate movement, has said it expects “somewhere between 50 to a couple of hundred people” to be involved in the planned protest on 13 September, with each person equipped with a drone.

“From 13 September, we will exploit a loophole in Heathrow airport’s health and safety protocols and fly toy drones within its restricted zone,” the group said. “It is our understanding that the airport’s authorities will respond by grounding all flights. Drones will not be flown in flight paths and there will be no risk of harm to anyone.