Former Kremlin economic adviser Andrei Illarionov was added to a registry of foreign agents, Russia's Justice Ministry said late on Friday, a designation the government applies to opponents.
People on the list may be closely monitored and are required to provide detailed information about their sources of income, expenses and a range of activities to the government or risk prosecution.
Illarionov, who resigned from the Kremlin in 2005 and moved to the United States, is critical of the Russian invasion of Ukraine and has called Russian policies of recent years "a catastrophe."
The Russian Justice Ministry said that Illarionov "spread false information" about Russian authorities and their decisions.
Illarionov did not immediately comment on the designation.