The Kremlin confirmed Anatoly Chubais has resigned from his position as special envoy to international organizations over Russia’s invasion of Ukraine. When contacted by Reuters, Chubais reportedly hung up the phone. Two sources told Reuters that Chubais left Russia with no plans to return.

Chubais was appointed to his envoy post in 2020. He was tasked with “achieving goals of sustainable development” after running state technology firm RUSNANO since 2008. In recent years, Chubais called for economic reform and was one of the most high-profile liberals associated with the Russian government.

The envoy’s resignation makes him the first senior official to break with the Kremlin since Russian President Vladimir Putin launched the Ukraine invasion a month ago. In that time, the Kremlin had appeared unified in Putin’s mission regarding Ukraine and even helped attempt to cut down on dissent among the Russian people.

“Any people, and even more so the Russian people, will always be able to distinguish true patriots from scum and traitors and simply spit them out like a fly that accidentally flew into the mouth, spit them out,” President Putin said last week. “I am convinced that such a natural and necessary cleansing of society will only strengthen our country.”

Outside of Russia, there has been near-universal opposition to the invasion, with China being the only notable exception. While not directly involving themselves in the war, NATO and the European Union have been providing aid to Ukraine and calling on Russia to end its invasion.

“By any measure, by even the shrewdest calculation, it is time to stop the fighting now and give peace a chance,” United Nations Secretary-General Antonio Guterres said Tuesday. “It is time to end this absurd war.”