UEFA reiterated its zero-tolerance policy on racism at a meeting in Sofia Thursday, encouraging referees to halt matches if need be and encouraging teams to denounce racism among fellow players and fans.

UEFA's executive committee said it "recommends and fully supports referees to stop matches in cases of racism and calls on national associations and leagues to do the same," in a resolution drawn up by the Professional Football Strategy Council (PFSC) and ratified Thursday.European football's governing body also called "on the players and coaches -- namely those with most influence on the perpetrators of racist acts -- to speak out, even if this may mean criticising their own fans or players."

The document was jointly adopted with the European Clubs Association (ECA) and the world players' union FIFPro.In January, AC Milan's Ghana international Kevin-Prince Boateng caused a sensation when he walked off the pitch during a friendly matchagainst Italian fourth division side Pro Patria after being showered with racist abuse by opposing fans.Several football officials, coaches and players spoke out against racism at games but some criticised Boateng's move, saying that walking out was not a solution.

"Many countries have taken significant and successful action but... such incidents are still widespread in our continent," UEFA said Thursday.It urged national leagues and disciplinary bodies to apply "stricter sanctions in cases of proven racism" to prevent recurrent offences and called on authorities "to play their part" and "arrest, prosecute and ban from stadia for significant periods those responsible for racist acts."