Russia's Khodorkovsky: Putin Is 'Naked King' Facing Economic Ruin, Discord

FILE - Mikhail Khodorkovsky (C) arrives at his first news conference after his release in Berlin, Germany, Dec. 22, 2013.

Former Russian tycoon Mikhail Khodorkovsky described Vladimir Putin on Thursday as a "naked king" and warned that the Kremlin chief is presiding over an economy that will weaken further, eventually provoking a battle between rival clans in Moscow.

"Putin with bare chest isn't a mighty leader: He is a naked king," Khodorkovsky told an audience in London.

Once Russia's richest man, Khodorkovsky was arrested in 2003 after falling foul of Putin only to be released in 2013 .

Khodorkovsky, who once controlled Russia's biggest oil company, said the Russian economy would weaken further and that eventually its weakness would provoke a battle between the powerful clans which dominate Russia.

In a message which likely to anger the 62-year-old Kremlin chief, the former tycoon also called on the West to build ties with Russian opposition groups in expectation of an end to the Putin era.

"Tomorrow when the regime changes you will have to build relationship and you will have very little time," said Khodorkovsky, 51. "I know what I'm saying as I witnessed two revolutions in Russia."