Recently while flying into the UK at Stansted Airport, I took a picture of a sign in the arrivals area pre-customs clearance. (The context is that when I travel, I like to take pictures of signs that I find amusing. Weird hobby, I know.)
This act was noticed by a member of staff - not someone from airport security or police, but someone assisting a wheelchair-bound traveller - who chased after me and asked me to delete the image since "photography was not allowed within the airport". She even ensured it was deleted from the phone's "deleted images" folder to prevent recovery.
I complied at the time with this request since it was late and I didn't want an argument but it got me thinking: what photography rights do people legally have, without prior media clearance, at UK airports? And if yes, is this restricted to certain areas before/after security and customs clearance?