Russia on Wednesday declared an independent election monitor a "foreign agent," one month before a parliamentary election in which President Vladimir Putin's unpopular United Russia party is expected to struggle.
Created in 2000, Golos had notably denounced election rigging in the 2011 parliamentary election and the 2012 presidential vote which saw Putin return to the Kremlin.
The Russian Justice Ministry included Golos, a local organization that observes elections, in its new list of "foreign agents."
The decision is likely to hamper the monitor's work during the Sept. 19 vote. Organizations designated as foreign agents have to carry out tedious administrative procedures and clearly indicate their status to the public under a controversial 2012 law.
The co-director of Golos, Grigory Melkonyants, told the Interfax news agency that the move was "an attack on the largest community of independent election monitors." He vowed that Golos will continue its work.
Golos trains election observers and also runs a hotline to which voters can report election violations. It runs both short and long term observations of Russia's elections.
"Our goal is free and fair elections in Russia," it says on its website.
While the organization was branded a foreign agent before, in 2013, it was then dissolved by a court three years later and had continued to function without a formal structure.
On Wednesday it was added to a list of organizations not registered with authorities that are financed from abroad.
During a constitutional referendum last year Golos said it had received hundreds of complaints of violations.