"It has been established that its activity presents a threat to the fundamentals of Russia's constitutional order and security," the Office of the Russian Prosecutor General said.
The Russian Justice Ministry announced on Friday that it had included the Free Russia Foundation in the list of undesired foreign non-governmental organisations.
According to the website of the organisation, it was founded in Washington in 2014 by a group of Russian emigrants. The Free Russia Foundation aims at informing US policy-makers on "events in Russia in real time" and supporting "formulation of an effective and sustainable Russia policy" in the United States. The Free Russia Foundation is chaired by David Kramer, former US state secretary for democracy, human rights and labour.