Russia says it is dissatisfied with the United States' fulfillment of its obligations according to their arms-reduction treaty.
RIA-Novosti reports Russia's Foreign Ministry said Saturday the U.S. has failed to provide assurances that some of its former nuclear missile launchers and bombers, now converted to accommodate conventional weapons, could not be retrofitted to again use nuclear arms.
Moscow also said U.S. authorities failed to stop leaks of radioactive materials and nuclear weapons-related information. In particular, it mentioned a 2006 case when police found that information from a nuclear research laboratory at Los Alamos, New Mexico, had been leaked to a criminal drug-dealing group.
The Foreign Ministry said such issues go against the terms of the Strategic Arms Reduction Treaty, known as START.
The United States has not yet responded.
Earlier this week, a key U.S. Senate panel put off its vote on whether to approve a new START agreement with Russia signed in April. The deal would make deeper cuts in both the U.S. and Russian nuclear arsenals.
Senate Foreign Relations Committee chairman John Kerry, a Democrat, said Tuesday that the panel will take up the treaty after the August recess. The committee must decide whether to send the treaty to the full Senate, where it needs a two-thirds majority for ratification.
U.S. President Barack Obama and Russian President Dmitri Medvedev signed the new treaty on April 8.
The treaty replaces the 1991 START agreement, which expired in December.
Some Republicans have said they want to make sure the new START treaty does not weaken the United States' ability to defend itself.
The Russian parliament must also ratify the new agreement before it takes effect.
Some information for this report was provided by Reuters.