Russian President Vladimir Putin says the government is still fighting to restrict the power of billionaire businessmen who made their fortunes after the fall of the Soviet Union.

The Russian leader told a judicial conference Tuesday in Moscow that authorities will continue their efforts against the influence of people he called "oligarchs."

Mr. Putin has pledged to crackdown on corporate corruption, and the giant Russian oil firm Yukos has been the center of an extensive government probe.

Officials say the company made its fortune through shady business deals after the fall of Communism and owes billions of dollars in back taxes.

Yukos says the efforts are retaliation against its former chief Mikhail Khodorkovsky for his support of the political opposition. The Kremlin has denied the charges. Mr. Khodorkovsky has been in prison for more than a year and is on trial on tax evasion and fraud charges.

Some information for this report provided by AP and AFP.