Heathrow Airport has slammed "reckless" plans by climate change activists to fly drones at the airport in protest at proposals for a third runway.
In a document seen by talkRADIO, Extinction Rebellion activists said they would attempt to "shut down" the airport by flying drones from nearby fields on June 18, unless there was an "immediate cancellation" of third runway plans.
And if their "demands" are not met, activists say they are prepared to stage a further 10 days of protest action.
But a spokesperson for Heathrow told talkRADIO that the action could "endanger lives".
“This is reckless action that if carried out could endanger the lives of the travelling public and our colleagues," the spokesperson said.
"We agree with the need to act on climate change, but that requires us to work together constructively – not commit serious criminal offences just as hardworking people prepare to spend a well-earned holiday with their family and friends.”
However, Extinction Rebellion maintain that their protest will be "wholly non-violent and peaceful", and say they will not fly drones whilst planes are in the air.
It is not the first time the activists have targeted Heathrow.
The group attempted to bring the airport to a standstill over Easter, but failed to disrupt flights.
Legislation was brought in last year which made it illegal to fly a drone above 400 feet or within 1km of an airport, with these offences carrying a fine of £2,500.