The press have been pretty shit on reporting the actual reasons behind this. From what I understand, given his recent performances both at the Euros (Semi Final & Final), World Cup (QF), CL Final recently - he has been told he isn't allowed to do big games at any of the next Euros or WC, or CL. The regulations about what he is allowed to do have meant he has reffed at the highest games possible, and won't be allowed to again. Shame. As refs go, he is one of the better ones IMO.