European Union (EU)
- (from 1957 )Belgium
- (from 1957 )France
- (from 1957 )Germany
- (from 1957 )Italy
- (from 1957 )Luxembourg
- (from 1957 )Netherlands
- (from 1973 )Denmark
- (from 1973 )Ireland
- (from 1973 )United Kingdom
- (from 1981 )Greece
- (from 1986 )Portugal
- (from 1986 )Spain
- (from 1995 )Austria
- (from 1995 )Finland
- (from 1995 )Sweden
- (from 2004 )Cyprus
- (from 2004 )Czech Republic
- (from 2004 )Estonia
- (from 2004 )Hungary
- (from 2004 )Latvia
- (from 2004 )Lithuania
- (from 2004 )Malta
- (from 2004 )Poland
- (from 2004 )Slovakia
- (from 2004 )Slovenia
- (from 2007 )Bulgaria
- (from 2007 )Romania