Chelsea's role in the resignation of the referee Anders Frisk will be scrutinised by Uefa's most senior figures at a meeting of the European governing body's executive committee next month.
Frisk announced his retirement following death threats from Chelsea fans - made after allegations about the Swedish referee by Chelsea's manager, Jose Mourinho - and the saga has sparked unprecedented fury among Uefa's executives.
The issue is now set to be added as an emergency item to the agenda for the executive committee meeting in Tallinn, Estonia, on 19 and 20 April. Possible measures to protect referees will be considered.
Uefa's treasurer, Dr Mathieu Sprengers, said: "We will certainly discuss it at the next executive committee meeting - it is a very serious matter when referees are threatened to such an extent that they give up the job. Coaches must also understand that the sort of people who make these threats - people who are no better than terrorists - can be stimulated by their remarks about referees. We must examine all the circumstances to see what can be done."
Sprengers, the president of the Dutch Football Association, added that match officials are turning their back on football due to abuse from managers and players.
He said: "In Holland we have lost 40 per cent of our referees over the last 10 years. Being a referee is now a very difficult profession."
Chelsea are refusing to apologise over the Frisk affair, or to withdraw their allegation that Frisk met the Barcelona coach, Frank Rijkaard, in the referee's room during the Champions' League last-16 first leg at the Nou Camp, which Chelsea lost 2-1.
Frisk and Rijkaard deny such a meeting took place, and the fourth official at the game, Martin Ingvarsson, has accused Mourinho of hounding the referee out of football.
Ingvarsson said: "What Chelsea are saying is a lie. No one came into our dressing-room and I don't know why they are saying it. I saw what happened. There was no chat between Anders Frisk and Frank Rijkaard. They shook hands in the tunnel before the game, not at half-time. They were together for a maximum of two seconds. There was no chat between them. I don't even know if they know each other that well.
"Maybe Anders has refereed at quite a few matches involving Mr Rijkaard. It is very sad that Anders has retired over this. He had done nothing wrong and had a good game."
The Uefa referees chief, Volker Roth, has rejected Mourinho's demand to apologise for calling the Chelsea manager "an enemy of football". He said: "I have heard Mourinho wants to sue me. I'm looking forward to that."
Chelsea can expect to be fined by Uefa next week for not attending the post-match press conference at the Nou Camp and for coming on to the pitch late after half-time. Uefa may also take individual disciplinary action against Mourinho - as they did against Sir Alex Ferguson two years ago when the Manchester United manager suggested the Champions' League draw may have been fixed.
Uefa is furious with Roman Abramovich's club, so much so that Uefa executives have not returned calls to those Chelsea officials who have attempted to repair relations.
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