MOSCOW, July 4 (RIA Novosti) - The World Boxing Association has approved a heavyweight title fight between former champions Nikolai Valuev of Russia and John Ruiz as the current titleholder Ruslan Chagaev of Uzbekistan is unable to defend it due to health problems.

Boris Dimitrov, a manager of the "The Beast from the East" Valuev (48-1, 34 KOs), said the bout had been tentatively set for August 30.

"The final decision on the date and place of the bout will be made in the next few days," he said. "The bout will be held either in Germany or the United States."

Valuev, 34, became the first Russian world heavyweight champion in December 2005 when he defeated John "The Quietman" Ruiz (43-7-1, 29 KOs). In April last year he lost his title to Ruslan "White Tyson" Chagaev from Uzbekistan.

Since then Chagaev (24 -0 -1, 17 KOs) held one title defense bout and was named recently as the "champion in recess" after he suffered ankle injury while sparring last week and had to undergo a surgery on his left torn Achilles tendon.

Chagaev's health problems have caused the postponement of two mandatory challenges with Valuev and on Thursday the WBA administration decided to sanction the bout with the Russian's closest contender, the Puerto Rican-American Ruiz.