A State Department report says the United States is uncertain whether Russia has fully complied with international treaties banning chemical and biological weapons.
The department Wednesday released its Compliance Report - an unclassified condensed version of a much more detailed report it sent to Congress. It says a lack of information from Russia has made it unclear if Moscow has fully complied with its obligations to get rid of all biological weapons.
The State Department also says it is still not sure if Russia has declared its stockpile of chemical weapons.
Russia has not yet replied to the report, which could have some bearing on the U.S. Senate's decision whether to ratify the new nuclear arms treaty signed earlier this year between Russia and the United States.
The report says Russia complied with what the State Department calls the "central limits" of the 1991 START nuclear arms treaty. But it says some of the more complex compliance questions remained unresolved when the treaty expired in December.
Some information for this report was provided by AFP.