Uefa has told the 12 Euro 2008 referees to clamp down on dissent in order to promote more respect in the game.
"Referees can accept a spontaneous expression of frustration from players," said the instructions.
"But (they) will firmly sanction players who show dissent to the referees by word or action."
Other issues they have been told to watch out for include pushing at corners, joining in mass confrontations and illegally using arms and elbows.
Uefa issued the instructions at a four-day workshop for the officials, who include England's Howard Webb, at their Euro 2008 base near Zurich, with six points highlighted in total.
The referees have been told to: "...act firmly (red card) against challenges involving excessive force... including the illegal use of arms and elbows".
"If a coach openly criticises the referee, action will be taken to curb his behaviour"
Holding and pushing in the penalty area at corners and free-kicks, along with "simulation", are other areas Uefa wants referees to combat.
Uefa will be able to review video evidence to take action over simulation - more commonly referred to as diving in the British game - at the finals, which take place between 7 & 29 June in Austria and Switzerland.
In an attempt to curb mass confrontations Uefa added: "Any players involved... have to realise that the main protester(s), including any who run over to join in, will get a yellow card."
It is not just players who have been targeted by European football's governing body as Uefa insists managers will also be under the microscope.
"If a coach openly criticises the referee, action will be taken to curb his behaviour," said Uefa.
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