Pavel Durov, the founder of VKontakte, Russia’s version of Facebook, resigned as CEO of the company today, saying he was unable to defend the network’s founding principles.

Durov, 29, has been slowly ceding control of the company to Alisher Usmanov, Russia’s richest man and a stalwart-Vladimir Putin ally. Durov sold his last 12 percent stake worth as much as $400 million to an ally of Usmanov’s in January, giving the oligarchy 52 percent control of the firm.

VKontakte has 228 million users around the world.

Durov’s departure from VK has been anything but smooth. In 2011, he rejected government requests to close political opposition accounts. He was accused of running over a traffic cop’s foot and was missing in action for several months, leading to a raid of VK offices and a sale by Durov’s co-founders to Ilya Sherbovich, another mega-rich Russian oligarch closely aligned with Putin.

TechCrunch is reporting that Durov has been under political pressure to ban VK pages for Alexei Navalny, a Russian dissident and frequent critic of Putin. Navalny’s Web presence was exterminated elsewhere when his authorities got his LiveJournal blog banned. LiveJournal is an immensely popular network in Russia today, so banning one of its blogs is akin to blacking out someone’s Facebook page here.

Durov left a short goodbye on VK, saying “It has become increasingly complicated to stick to the principles we once founded our social site upon.”

There is no word on who will replace Durov at the helm of the company.

H/T Gigaom | Illustration by Jason Reed