Wladimir Klitschko has not lost hope of defending his WBO, IBF, IBO titles against Russia's top heavyweight Alexander Povetkin, the WBA regular title holder.
Negotiations to bring the two together are thought to have collapsed several times over the last few years.
"I haven't lost hope, this would be a classy fight involving two world champions," the Ukrainian told R-Sport. "Even more so because Sasha hasn't lost a single fight," added Klitschko, referring to Povetkin using the Russian diminutive form of Alexander.
He claimed Povetkin's promoters were to blame for the fight never coming to fruition, without naming the precise culprit.
Povetkin is managed by Vlad Hrunov, who has organized several of his fights in Russia. German promoter Wilfried Sauerland has organized his bouts abroad.
"I'm ready, he's already been given chances," Klitschko said. "But we're not talking about the desire of Alexander Povetkin, but about that of his promoter. Sasha, unfortunately, doesn't take these decisions on his own."
Povetkin, the 2004 Olympic super heavyweight champion, has won all 24 of his professional fights, 16 of them by knockout.
Klitschko defended his titles from 40-year-old Tony Thompson in Switzerland in July, with a sixth-round knockout of the American for his 16th-straight career victory in the last eight years.
Klitschko's next defense has already been scheduled, against the American Arreola on November 10 in New York.