The move was passed by 175 votes to one at FIFA's annual congress in Sydney on Friday.

FIFA had been reluctant to sign up to the code, but signed a letter of intent in February at the UNESCO convention.

The latest version of the anti-doping code gives provision for flexibility of sanctions based on individual cases, something FIFA has long advocated.

World Anti-Doping Agency president John Fahey said: "I acknowledge the support given by FIFA to WADA and to the fight against doping in sport.

"The fight must go on, in the interest of sport and of public health.

"The commitment of FIFA has been strong and I believe it will be even stronger in the years to come.

"This document ratifies, reaffirms and endorses the commitment and cooperation that WADA and FIFA have and will continue to have in the future. I look forward to our continued cooperation.

"Your support will be noticed and followed by other sports in the world. I thank each of you."

FIFA president Sepp Blatter added: "We are convinced that together with president Fahey we will be able to show to the world what we, at FIFA, do for the fight against doping.

"We will also put at the disposal of WADA all of our medical officers all around the world."

The code will be officially incorporated into FIFA's rules next year.