Russian Investigative Committee (IC) issued an arrest warrant Monday for Dmitry Yarosh, leader of Ukraine's radical Right Sector movement.
"The case (against Yarosh) was opened on two articles of the Russian Criminal Code -- public calls for extremism and public calls for terrorism," Xinhua quoted committee spokesman Vladimir Markin as saying in a statement.
According to the committee, Yarosh publicly urged anti-Russian forces to conduct extremist and terrorist actions in Russian territory.
It sought to arrest Yarosh "in absentia" and put him on the international wanted list, Markin added.
On Saturday, Yarosh, via a Russian social network, called on Chechen warlord Doku Umarov to help the Ukrainian ultra-nationalist movement in a joint fight against the Russian government.
Russia's parliament Saturday authorised President Vladimir Putin to use military force to protect Russia's interests in Ukraine.