September 26, 1997


The Treaty Between the United States of America and the Union of Soviet Socialist Republics on the Limitation of Anti-Ballistic Missile Systems of May 26, 1972, commonly known as the ABM Treaty, was a bilateral agreement between the two states. When the USSR dissolved at the end of 1991, and its constituent republics became independent States, the only operationally-deployed ABM system was at Moscow, while a number of its early warning radars and an ABM test range were located outside of the Russian Federation. Although the ABM Treaty continues in force, it nevertheless has become necessary to reach agreement as to which New Independent States (NIS) would collectively assume the rights and obligations of the USSR under the Treaty.

The Memorandum of Understanding on Succession (MOUS) establishes that the Parties to the ABM Treaty shall be the United States, Belarus, Kazakhstan, the Russian Federation, and Ukraine. For the purposes of the MOUS and the ABM Treaty, the latter four states are considered to be the USSR Successor States. Pursuant to the MOUS provisions, the USSR Successor States collectively assume the rights and obligations of the USSR. This means that only a single ABM deployment area is permitted among the four Successor States; in addition, only 15 ABM launchers at ABM test ranges are collectively permitted. Russia will be able to continue to operate any existing early warning radars, as well as the ABM test range, located within other states with the permission of those governments.

States that become bound by the MOUS also are bound to observe the provisions of both the First and Second Agreed Statements, which deal with lower-velocity and higher-velocity theater ballistic missile defense systems, respectively. These agreements will now be subject to ratification or approval by the signatory states in accordance with the appropriate constitutional procedures of each state, and will enter into force on the date when the governments of all five signatory states have deposited instruments of ratification or approval of the Memorandum of Understanding on Succession. The MOUS will remain in force as long as the ABM Treaty remains in force. The ABM Treaty is of unlimited duration.