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U.S. Department of State
96/02/01 Fact Sheet: Start II
Bureau of Public Affairs
FACT SHEET
Treaty on the Further Reduction and Limitation
of Strategic Offensive Arms (START II)
What is START II?
The START II treaty is a bilateral treaty negotiated by the United
States and Russia during 1991 and 1992. It was signed by Presidents
Bush and Yeltsin on January 3, 1993.
START II builds on the foundation of START I to create an equitable and
effectively verifiable agreement that reduces the number of strategic
delivery vehicles (ballistic missiles and heavy bombers) and the number
of warheads deployed on them. Overall strategic forces will be reduced
by 5,000 warheads in addition to the 9,000 warheads being reduced under
START I.
Key Provisions of START II
Because START II builds upon the START I treaty, START I remains in
effect. START II will remain in force throughout the duration of START
I, which has a 15-year duration and can be extended for successive 5-
year periods by agreement among the Parties to the treaty.
START II sets equal ceilings on the number of strategic nuclear weapons
that each Party may deploy. The final ceilings will be reached in two
phases. Phase One is to be completed seven years after entry into force
of the START I treaty (which was December 5, 1994). Phase Two is to be
completed by 2003. However, Phase Two may be completed by the end of
2000 if the United States is able to provide financial assistance for
the elimination of strategic offensive arms in Russia.
By the end of the first phase, each Party must have reduced the total
number of its deployed strategic warheads to 3,800-4,250. This includes
warheads on deployed intercontinental ballistic missiles (ICBMs),
warheads on submarine-launched ballistic missiles (SLBMs), and the
warheads carried on heavy bombers with nuclear missions. No more than
1,200 warheads may be on deployed ICBMs with multiple reentry vehicles
(MIRVs); no more than 2,160 on deployed SLBMs; and no more than 650 may
be on deployed heavy ICBMs.
By the end of the second and final phase, each Party must have reduced
the total number of its deployed strategic warheads to 3,000-3,500. Of
those, none may be on MIRVed ICBMs, including heavy ICBMs. No MIRVed
ICBMs will be deployed by the end of the second phase. No more than
1,700-1,750 warheads may be on deployed SLBMs. There will be no
prohibition on MIRVed SLBMs.
Downloading
START II allows for a reduction in the number of warheads on certain
existing MIRVed ballistic missiles. This is called "downloading." Such
downloading will be permitted in a carefully structured fashion, which
is a slight variation from the rules agreed in START I.
-- Each side will be able to download two existing types of ballistic
missiles by up to four warheads each.
-- No more than 105 ICBMs of one of those types may be downloaded by up
to five warheads each. Such an ICBM may only be deployed in silos in
which it was deployed at the time the two START treaties were signed.
Thus, the three-warhead U.S. Minuteman III ICBM, the four-warhead
Russian SS-17 ICBM, and 105 of the six-warhead Russian SS-19 ICBMs may
be downloaded to a single warhead, to comply with the requirement to
eliminate all MIRVed ICBMs.
The Russian SS-18 heavy ICBM and launchers for the SS-24 ICBM would be
destroyed. SS-24 ICBMs would be eliminated in accordance withÊSTART
procedures.
Missile-System Elimination
In START I, deployed SLBMs and most deployed ICBMs may be removed from
accountability either by destroying their launchers or, with the
exception of SS-18 silos, by converting the launcher so that it is only
capable of launching another type of missile. Moreover, 154 SS-18 silos
must be eliminated through destruction under START I.
Under START II, those rules will continue to apply, but with the major
exception of the SS-18. Ninety SS-18 silos may be converted to launch a
single-warhead ICBM, which Russia has said will be a variant of the SS-
25. The START II treaty provisions specify conversion procedures which
are subject to inspection and which are virtually irreversible without
destroying the silo.
In addition to the elimination or conversion of SS-18 silo launchers,
all SS-18 ICBMs, whether deployed or non-deployed, must be eliminated no
later than January 1, 2003. This is a major improvement on START I,
which did not require the destruction of silo-based missiles. Moreover,
this provision achieves the long-standing U.S. goal of totally
eliminating heavy ICBMs.
Heavy Bombers
Under START II, heavy bombers will be attributed as carrying the actual
number of weapons--whether long-range air-launched cruise missiles
(ALCMs), short-range missiles, or gravity bombs--for which they are
equipped. This number is specified in the treaty's Memorandum of
Attribution and is subject to confirmation by a one-time exhibition of
the bombers and by on-site inspections.
This attribution formula is another improvement over START I. Under
START I, the first 150 U.S. heavy bombers equipped to carry long-range
ALCMs are attributed with 10 warheads; each bomber in excess of the 150
would be attributed with the actual number of long-range ALCMs it is
equipped to carry. For the former Soviet Union, the first 150 heavy
bombers are attributed with eight warheads; each heavy bomber in excess
of 150 would be attributed with the number of long-range ALCMs it is
equipped to carry. For both Parties, all heavy bombers equipped to
carry nuclear weapons other than long-range ALCMs are attributed with
one warhead each.
Up to 100 heavy bombers that were equipped for nuclear arms other than
long-range ALCMs may be reoriented to a conventional role and exempted
from accountability under START II. Such bombers will be based
separately from heavy bombers equipped to carry nuclear weapons, they
will be used only for non-nuclear missions, and they must have
observable features that differentiate them from nuclear-equipped heavy
bombers of the same type. If these heavy bombers are returned to a
nuclear role, which is permitted, they will become accountable under
START II and may not be returned to their exempted status.
Verification
The comprehensive, intrusive START I verification regime also will apply
to START II. Additionally, START II has new verification measures.
These include the following:
-- Observation of the conversion of SS-18 silos;
-- Observation of SS-18 eliminations;
-- Exhibitions of heavy bombers to allow confirmation of capacity; and
-- Exhibition of reoriented bombers to confirm their observable
differences.
Moreover, reentry vehicle inspections (RVOSI) will allow inspectors
visual access to the front ends of ICBMs and SLBMs to verify that the
numbers of warheads attributed to those systems match the number
deployed on them.
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