Russian officials this week carried out a secret inspection of the U.S. strategic missile defense base in California as part of the New START arms treaty, according to Obama administration officials.
The inspection of five missile defense interceptors is the only one allowed under the 2010 arms accord. The treaty requires cuts of U.S. and Russian deployed strategic warheads to 1,550.
A defense official said the visit was a treaty verification visit hosted by the Defense Threat Reduction Agency.
A State Department official declined to comment on the inspection but confirmed it was related to New START. "Implementation activities under New START are confidential," the official said.
However, Thomas Moore, a former Senate Foreign Relations Committee professional staff member, said the inspection of the base was a controversial part of U.S. and Russian arms talks leading up to New START that was ratified by the Senate in December 2010.
The United States had opposed including the five Ground-Based Interceptor (GBI) silos in the treaty inspection terms, said Moore, a specialist on arms control issues.