Russia's Investigative Committee says it has launched a criminal inquiry against Ilya Ponomaryov, the lone State Duma representative to vote against the 2014 annexation of Crimea from Ukraine.
Ponomaryov, a member of the A Just Russia party, is accused of embezzling money earmarked for the Skolkovo science and technology park project outside Moscow.
Investigative Committee spokesman Vladimir Markin said on June 9 that since Ponomaryov was currently residing outside Russia, the committee planned to seek an international arrest warrant for him.
In April, Russia's State Duma, the lower house of parliament, voted to strip Ponomaryov's immunity from prosecution.
Lawmakers from A Just Russia announced on June 8 that they had begun the process of stripping Ponomaryov of his parliamentary mandate.
Sergei Mironov, leader of the party's parliamentary faction, told reporters in Moscow that the move had nothing to do with the charges faced by Ponomaryov, but with the fact that Ponomaryov had not attended parliamentary sessions since September.
In August 2014, Ponomaryov was reported to be living in the United States, prompting Russian authorities that month to freeze the lawmaker's bank accounts and to announce that he would not be allowed to return to Russia.
He is believed to be living in California.
Authorities accuse Ponomaryov, one of a handful of opposition lawmakers in the State Duma, of embezzling some 22 million rubles (about $393,000) earmarked for the Skolkovo technology hub.
Ponomaryov denies wrongdoing and says the embezzlement allegations are politically motivated.
In April, Ponomaryov told RFE/RL that he did not plan to apply for political asylum in any foreign country.
"I do not intend to become a political emigre," Ponomaryov said. "I ended up here [in the United States] against my will. They intentionally waited until I was abroad on business to close the border to me. I am a Russian citizen. I am a deputy from Novosibirsk and I intend to remain such in the future."
Ponomaryov was the only Duma member to vote in March 2014 against a treaty to annex Crimea from Ukraine, preventing a unanimous show of support in the 450-member body.
The vote paved the way for the Crimean Peninsula to be absorbed by Russia, a contentious move that has not been recognized by the international community.
He told RFE/RL that he voted "absolutely correctly and would vote in exactly the same way again."
With reporting by RFE/RL's Russian Service and Interfax