The referees' union that represents Mark Clattenburg has called on Chelsea to issue a formal apology to the official after he was cleared of alleged racism.
The Football Association announced on Thursday that they would not be charging Clattenburg following allegations from Chelsea that he racially abused John Obi Mikel at the end of last month's Premier League defeat to Manchester United at Stamford Bridge.
The FA has instead charged Chelsea midfielder Mikel with misconduct.
"We are seeking a full and unreserved apology and compensation for loss of earnings, damage to reputation and stress," said Prospect's Alan Leighton.
Clattenburg released a statement on Thursday expressing his relief at being cleared of all charges.