A close ally of President Vladimir Putin warned Western governments on Thursday that a nuclear war would ensue if they gave the green light for Ukraine to use long-range Western weapons to strike targets deep inside Russia.

The Kremlin has had little success invoking its nuclear arsenal to deter Ukraine and the West from using new tactics to stop Russia’s invasion. That may be changing.

A senior Russian lawmaker on Thursday said that Ukrainian strikes on Russia with Western missiles would lead to global war with the use of nuclear weapons and that Moscow's response would be tough with more powerful weapons.

Armenia's prime minister said the CSTO, seen as Putin's NATO, "creates threats" for his country's future existence, after it pulled away from it.

Dmitry Peskov, the spokesperson for Kremlin leader Vladimir Putin, has stated that NATO's refusal to take Vladimir Putin's statements seriously regarding the supposed consequences of allowing Ukraine to attack Russian territory with long-range Western weapons is "provocative and dangerous".

On Wednesday, the Kremlin condemned comments by outgoing NATO chief Jens Stoltenberg as “dangerous”, Reuters reports. Stoltenberg had suggested that allowing Ukraine to use Western long-range missiles to strike Russian territory would not trigger an escalation from Moscow.

Vladimir Putin is 'fully ready' to detonate a nuclear bomb in the Arctic and take the world down a path it has not trodden since the Cold War, Kremlin officials have warned