CND believes the renewal of the recently expired New START Treaty is vital to ensure nuclear security in an increasingly dangerous world. London CND Chair Carol Turner explains why.
START, the Strategic Arms Reduction Treaty between the United States and the Russian Federation is the largest and most complex arms control treaty ever. By late 2001 START had resulted in the removal of around 80% of all strategic nuclear weapons then in existence.
In 2026, the US and Russia between them possess over 90% of the world’s nukes. On 5 February this year however, New START the current version of the Treaty expired without a replacement. Its demise removes the limitations on the world’s two largest nuclear arsenals, which have been in place for over a quarter of a century. This is a retrograde step for global arms control, and comes at a time when the world is closer to nuclear war than ever before. The end of New START clears the way for a new nuclear arms race that threatens us all.
In February 2021, the US and Russia agreed to extend the Treaty by five years. Two years later, Russia suspended its participation in New START though it did not withdraw from the Treaty. This was prompted by escalating tensions with the US and NATO over the war in Ukraine, along with accusations that the US was undermining the Treaty's purpose. President Putin framed the decision as a response to the Western objective of inflicting a ‘strategic defeat’ on Russia and accused the US of attempting to use the Treaty’s provisions to assist Ukraine in the war.
In September last year, however, Putin proposed that the US and Russia continued to observe the main limits of New START for a further year after its expiry date. The US did not respond.
CND is campaigning for the renewal of New START, and holding demonstrations at the US and Russian Embassies, to coincide with the nuclear Non-Proliferation Treaty (NPT) Review Conference which takes place between 27 April and 22 May 2026.
What follows is a summary of START negotiations, and a short explanation of what the Treaty covered. (1)
Overview
START dates back to 1985, when discussions between the then US President Ronald Reagan and Soviet President Mikhail Gorbachev began. The Strategic Arms Reduction Treaty comprises of START I, START II, The Lisbon Agreement, and New START. The latter, signed in April 2010, was the latest version of a bipartisan agreement to verifiably reduce the US and Russian strategic nuclear arsenals.
In July 1991, the US and USSR signed the original Treaty, five months before the dissolution of the USSR. Thereafter, further discussion took place between Presidents George Bush Snr and Boris Yeltsin and resulted in the Lisbon Protocol, signed in May 1992, by which the newly independent states of Belarus, Ukraine, and Kazakhstan which possessed Soviet strategic nuclear weapons, committed to START as well as the Russian Federation and the US. The two parts of the negotiations to establish the Treaty were thereafter referred to as START I and START II, in recognition of Russia’s changed status. START II took effect from December 1994.
In a nutshell, the Treaty banned the signatories from deploying more than 6,000 nuclear warheads and 1,600 intercontinental ballistic missiles (ICBMs) and bombers, and made provision for on-site inspections and detailed data exchanges. A Bilateral Consultative Commission (BCC) comprising diplomats, military officials, and technical experts from the US and Russia was established to oversee the implementation of the Treaty’s terms.
New START was signed 2010 and came into force for five years on 5 February 2011. It replaced START which expired in December 2009, and superseded the 2002 Strategic Offensive Reductions Treaty (SORT).
Treaty provisions
The Treaty set limits on the deployed nuclear arsenals of the US and Russia – ie those parts of each country’s nuclear forces which were available for immediate use in combat. The Treaty did not cover weapons and warheads that are stored, reserved, or inactive, and therefore not immediately available.
New START:
limited the number of deployed strategic nuclear warheads and bombs.
The figure was set at 1,550. This was down by about 74% on the warheads and bombs allowed under START I, and around 30% below the limits set by SORT.limited the number of deployed missiles, bombers and launchers.
Intercontinental ballistic missiles (ICBMs), submarine-launched ballistic missiles (SLBMs), and heavy bombers assigned to nuclear missions were limited to 700. Deployed and non-deployed ICBM launchers, SLBM launchers, and bombers were limited to 800. The latter restriction was intended to prevent the US and Russia from retaining large numbers of non-deployed launchers and bombers.monitored the number of non-deployed ICBMs and SLBMs.
The Treaty provided for location data and on-site inspections in order to confirm these ballistic missiles were not added to the deployed force.
What you can do
Join CND at the Russian Embassy in London on Thursday 30 April, 12 noon to 2pm, to call for the renewal of New START. A similar protest will be held at the US Embassy on Thursday 21 May. Visit CND website for more details about the protests.
1: More detailed accounts of the provisions of New START are available from the Arms Control Association and Union of Concerned Scientists. By way of comparison, the Federation of American Scientists provides an inventory of the world’s total nuclear forces in 2025, both deployed and non-deployed.