If an operation is within a reasonable distance from any airport, a UK licensed drone pilot will always make contact with the local ATC, be it near Heathrow or a small flying club airfield. It ensures everybody in the vicinity is in the know. They are always cooperative and thankful. Many operators will also listen to ATC radio traffic as an additional safety measure. Actually the local ATC cannot give a drone operator permission to be in the area but merely makes note of their presence.