London, Oct.11 Angry referees have snubbed Manchester United coach Sir Alex Ferguson's apology to referee Alan Wiley.

Last night, the referees' union Prospect threatened to sue Fergie for his accusatory statement against Wiley after last Saturday's 2-2 draw with Sunderland.

According to a News of The World report, the referees union is furious that Fergie appeared to question the fitness of all referees in his statement.

Alan Leighton, national secretary of Prospect, insists Ferguson's response only "cranked up" his apparent belief that referees like Wiley are not fit enough to do their job.

Leighton told the Sport of the World: "If the FA don't satisfy us, we would have to take legal advice. Any issue of defamation would be against Sir Alex."

He warned that the referee's union would also demand a showdown with the FA about their disciplinary system if Fergie is cleared on the basis of a statement they refuse to accept.

Leighton insists the Red Devils chief should still be hit with a UEFA-style coaching ban. (ANI)