The Ukrainian boxer defended his title belts in Germany on Saturday, knocking out Rahman in the seventh round.
"The head of state wished the prominent athlete good health, endless inspiration and new victories in the name of Ukraine," a spokesperson for President Viktor Yushchenko said.
The 32-year-old Ukrainian, who lives and trains in Germany, was initially scheduled to fight Alexander Povetkin (16-0, 12 KOs), but the bout was canceled last week when the Russian suffered an injury in training.
The promoters decided not to cancel the fight in Mannheim, Germany, and reached an agreement to replace Povetkin with two-time heavyweight world champion Rahman (45-7-2, 36 KOs).
All four heavyweight championship titles currently belong to boxers from the former Soviet Union: Wladimir Klitschko holds the IBF and WBO titles, his older brother Vitali Klitschko holds the WBC belt, and Russia's Nikolai Valuev is the WBA champion.
