At the dissolution of the Soviet Union in 1991, Soviet nuclear weapons were deployed in four of the new republics: Russia, Ukraine, Belarus and Kazakhstan. In May 1992, these four states signed the Lisbon Protocol, agreeing to join the Treaty on the Non-Proliferation of Nuclear Weapons, with Russia the successor state to the Soviet Union as a nuclear state, and the other three states joining as non-nuclear states.
Ukraine agreed to give up its weapons to Russia, in exchange for guarantees of Ukrainian territory from Russia, the UK and the USA, known as the Budapest Memorandum on Security Assurances. China and France also made statements in support of the memorandum.
The exact number of nuclear warheads is a state secret and is therefore a matter of guesswork. The Federation of American Scientists estimates that Russia possesses 4,300 nuclear warheads, while the U.S. has 4,000; Russia has 1,950 active strategic nuclear warheads, compared with the U.S. having 1,650. On the other hand, Russia is estimated to have roughly 1,500 tactical nuclear weapons, all of which are declared to be in central storage.
The RS-28 Sarmat (Russian: РС-28 Сармат; NATO reporting name: SATAN 2), is a Russian liquid-fueled, MIRV-equipped, super-heavy thermonuclear armed intercontinental ballistic missile in development by the Makeyev Rocket Design Bureau from 2009, intended to replace the previous R-36 missile. Its large payload would allow for up to 10 heavy warheads or 15 lighter ones or up to 24 hypersonic glide vehicles Yu-71, or a combination of warheads and massive amounts of countermeasures designed to defeat anti-missile systems; it was heralded by the Russian military as a response to the U.S. Prompt Global Strike.
In 2015, information emerged that Russia may be developing a new nuclear torpedo, up to 100 megatons , the Status-6 Ocean Multipurpose System, codenamed “Kanyon” by Pentagon officials. This weapon is designed to create a tsunami wave up to 500m tall that will radioactively contaminate a wide area on an enemy coasts with cobalt-60, and to be immune to anti-missile defense systems such as laser weapons and railguns that might disable an ICBM. Two potential carrier submarines, the Project 09852 Belgorod, and the Project 09851 Khabarovsk, are new boats laid down in 2012 and 2014 respectively. Status 6 appears to be a deterrent weapon of last resort. It appears to be a torpedo-shaped robotic mini-submarine, that can travel at speeds of 185 km/h (100 kn). More recent information suggests a top speed of 100 km/h (54 kn), with a range of 10,000 km (6,200 mi) and a depth maximum of 1,000 m (3,300 ft). This underwater drone is cloaked by stealth technology to elude acoustic tracking devices.