Any controller who holds an ATC Licence that's compatible with the new European Harmonised ATC Licence as detailed in publication ESARR5 is eligible to work in one of the 'participating states'.
You would need to satisfy the National Supervising Authority (in the UK's case, the Civil Aviation Authority's SRG) regarding:
1. ATC Training - this must at least comply with the ESARR5 Common Core Content.
2. Proficiency in Spoken English - I believe this is Oxford Level 5 (based on the required ICAO Standard).
3. Successful completion of any conversion training required to become conversant with national legislation and national procedures, where these differ from the country in which you are currently employed.
These requirements are not UK exclusive and will be applied by any 'participating state' - however, in non English-speaking countries you would also have to demonstrate proficiency in speaking the language of that country in order to be able to efficiently co-ordinate with other controllers and units.
Go to Eurocontrol's website and search for ESARR5 (the requirements document).
Go to the UK CAA's website and search for CAP744 (the UK's defining document that subsumes ESARR5).
Then go to the NATS' website and search for recruitment.
Personally, I can't imagine why you'd want to leave a warm and sunny climate where the wine is cheap and the people friendly, to work in a cold, damp, crowded and expensive place like the UK - fancy a job swop...???
Good luck anyway!
