(Reuters) - Video Assistant Referees (VAR) must not show the "wrong idea of solidarity" by appearing to protect officials who make mistakes on the pitch, the head of FIFA's Referees' Committee has said.
Speaking at the World Football Summit, Italian Pierluigi Collina also stressed the importance of on-field referees using pitchside monitors during games to review decisions.
"Another thing to be considered (is) a sort of wrong idea of solidarity," Collina said. "If you belong to a team, you always try to protect your team mates. If your team mate made a mistake you try to find everything to say 'no, no, no, he was correct'.
"It's a sort of friendship I'd say. Referees must understand the solidarity and friendship that they want to show is to tell their colleague 'be careful, you might have made a mistake'.
"'It's better that you have another chance watching the incident on a monitor, you have assessed probably wrongly,' so that finally you can avoid a mistake."
Former World Cup referee Collina, 60, said wrong decisions taken in important games can "really kill a referee's career."
"VAR is a very important safety net," he added.
The VAR was involved in controversy during the last round of Premier League matches, prompting Tottenham Hotspur manager Jose Mourinho to say that match officials should be obliged to explain their decisions.
Mourinho was left baffled after Harry Kane was denied what looked a clear penalty early in the 0-0 draw at Bournemouth on Thursday, even though it was referred to the VAR officials.
On the same night Bruno Fernandes earned Manchester United a penalty at Aston Villa despite appearing to step on Ezri Konsa's leg.