Recent reports suggested some European nations would consider boycotting the tournament due to the conflict in neighbouring Ukraine.
However, Blatter warned against such action on Tuesday, claiming that nothing good would come of it and comparing the situation to Russia's hosting of the 2014 Winter Olympics.
"FIFA unconditionally supports the staging of the World Cup by Russia," he said. "A boycott will never give any positive effect. We trust the country, its government.
"Russia is the world's biggest country. You know, Russia is in the eye of the international media. Football cannot only unite Russia but show the whole world that it is stronger than any protest movement.
"There was the same situation ahead of Sochi, but neither during nor after the Games, has there been a single word against these Games."
And Blatter revealed he was confident all venues would be ready for the 2018 tournament.
He added: "I can say that in comparison with Brazil [2014 hosts], Russia is considerably ahead of schedule with four years remaining before the event's start."
