FIFA anti-racism adviser Tokyo Sexwale believes black players could boycott the 2018 World Cup and urged Russian President Vladimir Putin to demand tougher action against racism in football. Sexwale, who was an anti-apartheid campaigner and former political prisoner on Robben Island, is against a boycott but expressed concern in an interview about the growing number of racist incidents in the Russian league.

“There is a threat black players will say they are not going to Russia (for the World Cup), we can’t have that,” Sexwale said Tuesday on the sidelines of the Doha Goals conference.

“I am talking as a FIFA person and a citizen of the world, it can’t go that far. …Once these things start and you don’t act as leaders, these things snowball.”

Although UEFA has punished Russian clubs for racism at Champions League matches in recent years, the national federation has appeared less willing to tackle abuse. Sexwale is urging his “personal friend” Putin to intervene.