Mach78--
It's illegal to listen to just about anything in the UK, unless you have a licence. According to the Radiocommunications Agency:
"Although it is not illegal to sell, buy or own a scanning or other receiver in the UK, it must only be used to listen to transmissions meant for GENERAL RECEPTION. The services that you can listen to include Amateur and Citizens' Band transmissions, licensed broadcast radio and weather and navigation broadcasts.
It is an offence to listen to any other radio services unless you are authorised by the Secretary of State to do so. "
The full document's at
http://www.radio.gov.uk/document/ra_info/ra169.htm and gives chapter and verse.
Welcome to Edwardian Britain...
R