FIFA formally signed the new World Anti-Doping code on Friday during its annual Congress in Sydney.

FIFA president Sepp Blatter jointly signed the agreement with WADA boss John Fahey after the Congress voted overwhelmingly in support of the resolution.

Soccer's world governing body had previously been reluctant to sign the agreement because it was opposed to some of WADA's (World Anti-Doping Agency) rules, including uniform two-year bans for athletes caught using performance-enhancing drugs.

However, FIFA agreed to sign the accord after WADA proposed a revised set of rules that were endorsed by sporting bodies at a doping conference in Spain last year.

"The commitment of FIFA has been strong and I believe will be even stronger in the days ahead," Fahey told the Congress.

"Football is a giant in the universe of team sport and your example is of paramount importance.

"Your support will be noticed and followed by other team sports around the world."

The new anti-doping code, which comes into force on January 1 2009, will allow greater flexibility in the sanctions imposed on athletes who can prove they failed doping tests through oversight rather than an intention to cheat.

It will also define new standards relating to the 'whereabouts' rules, in which athletes have to inform anti-doping authorities of their location for potential testing.

FIFA was one of the last Olympic sport federations to accept the WADA code, finally doing so at its 2004 Congress in Paris.

Even then there were differences between the two bodies, with the Court of Arbitration for Sport telling FIFA in 2006 that its anti-doping regulations did not fully comply with those of WADA.

FIFA has been particularly keen to maintain flexibility in the case of sanctions imposed on first time doping offenders, preferring to treat each offence on a case-by-case basis rather than implementing the mandatory two-year ban previously favoured by WADA.

The new WADA code will allow for such flexibility -- enabling federations to hand down lesser punishments and even exonerations where there are mitigating circumstances.

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