FIFA has opened disciplinary proceedings against Croatia defender Joe Simunic for leading an apparent pro-Nazi chant with fans after his team qualified for the World Cup. 

Croatia's public prosecutors have already fined Simunic $4,300 for "spreading racial hatred" after he took up a microphone following Tuesday's playoff match against Iceland and shouted to supporters: "For the homeland!"

The fans responded: "Ready!" 

The call was used by the Croatian pro-Nazi puppet regime that ruled the state during World War II. 

Simunic has defended his action, saying he was driven by love for his country.