Iskander-M nuclear-capable missiles

Context

Russia has promised Belarus Iskander-M nuclear-capable missiles.

The Iskander-M is a mobile guided missile system codenamed "SS-26 Stone" by NATO, which replaced the Soviet "Scud."
Iskander-M is a term used by Russia to define both the transporter-erector launch system and the short-range ballistic missile (SRBM) it fires.
Iskander-M systems can fire ballistic and cruise missiles, both conventional and nuclear types.
The system can also fire ground-launched cruise missiles (GLCMs) – the SSC-7 and the SSC-8.
Range: The systems have a range of up to 500km (310 miles).
The Iskander-M system has been exclusively used by the Russian military.
It can carry conventional and nuclear warheads up to 700 kg and employs a maneuverable re-entry vehicle (MaRV) and decoys to defeat theater missile defence systems.
Conventional warheads that can be equipped by the Iskander include cluster warheads, fuel-air explosives, bunker-busters, and electromagnetic pulse (EMP) warheads.

There are two versions of the missile

While the Iskander system was inducted by Russia in 2006, its development picked pace in the late 1980s after the “Oka” SRBM or the OTR-23 was banned under the Intermediate Nuclear Forces Treaty.
The Oka was Russia’s first attempt to replace the Soviet Scud missiles. Iskander was the second.
Russia first used the Iskander in combat in Georgia in 2008.