Russia's lower house of parliament, the Duma, on Friday gave preliminary approval to a historic nuclear weapons reduction pact with the U.S.
Final ratification is not expected until next year.
Lawmakers voted 350-58 in favor of the New Strategic Arms Reduction Treaty in the first of three required readings of the accord.
The two additional readings are not expected to happen until January 2011. Senior lawmaker Konstantin Kosachev, says further work on the treaty will continue once the Duma resumes meeting in January.
He has been quoted as saying START as it was voted for by the U.S. Senate this week contains a large number of interpretations that require study and response from the Russian lawmakers.
The U.S. Senate voted 71-26 in favor of the accord.