Leading FIFA sponsor Adidas says the corruption allegations surrounding world football's governing body could be harming the sport and its backers.

FIFA is facing its biggest crisis since the sportswear maker became a commercial partner more than 30 years ago, with investigations under way into eight members of the ruling body.

In the most high-profile case, presidential candidate Mohamed bin Hammam and FIFA vice president Jack Warner have been accused of bribery by American executive committee member Chuck Blazer.

Asked about the problems facing FIFA ahead of the presidential election, Adidas said in a statement: ''the negative tenor of the public debate is neither good for the sport of football nor for FIFA as an institution and its partners.''