Russia's Foreign Ministry said Saturday it is dissatisfied with the U.S.'s fulfillment of its obligations under bilateral nuclear arms reduction treaties.

The ministry also accused the U.S. of failing to properly safeguard radioactive materials.

In particular, the ministry said, the U.S. has failed to provide assurances that some of their nuclear missile launchers and bombers converted to carry conventional weapons couldn't be retrofitted.

U.S. authorities also have failed to prevent leaks of radioactive materials and nuclear weapons-related information, the ministry claimed.

"In the period of the validity of START 1 (Strategic Arms Reduction Treaty), Russia's concerns in regard to the observance of the treaty by the U.S. were not allayed," the ministry said in a statement published on its website.

"For example, notices and telemetric data were not provided to the Russian side in advance with regard to a number of Trident-II submarine-launched missile flight tests carried out at the Eastern Range," the ministry said.

The ministry said "uncontrolled activities" on the part of the U.S. deprived Russia of the possibility of monitoring one of the key parameters under the 1991 START-1 treaty.

The U.S. also violated the Intermediate-Range Nuclear Forces Treaty (INF), the ministry noted.

In addition, American companies continue to supply missile technology related products and know-how to foreign countries, about third of which are not members of the Missile Technology Control Regime, including Egypt, Israel, Kuwait, Oman, the UAE, Taiwan and others, the statement said.

Questions were also raised in connection with American weaponry supplied to Israel during the last Middle East conflict.

The ministry also said the U.S. violated a number of other terms of the treaty, including provisions on chemical and biological weapons.

Russia and the United States signed a new START treaty on April 8, replacing the START 1 that expired in December.