British Prime Minister David Cameron and United States President Barack Obama are facing calls to take financial action against the likes of Roman Abramovich, the Chelsea soccer club owner, over Russia's annexation of Crimea.
A prominent Russian opposition politician said Western Governments' response to the Crimean crisis should include seizing the assets of wealthy Russian businessmen, such as Abramovich and Alisher Usmanov, a shareholder in the Arsenal club.
So far, Western sanctions imposed in protest at Russian aggression in Ukraine have fallen on Russian politicians and officials.
But Alexei Navalny, a leading critic of Russian President Vladimir Putin, said the sanctions should be aimed at billionaire "oligarchs" with close links to Putin.
Navalny said the West should take action including "freezing the oligarchs' financial assets and seizing their property".