Putin's atomic sabre-rattling points to even greater hostilities between Russia and the West | Deborah Haynes
Russia's president had a message of defiance for the West as he suspended participation in the last major nuclear arms control treaty with the United States.
Vladimir Putin also vowed to conduct nuclear weapons tests if Washington chose to do so and challenged the nuclear weapons posture of the UK and France.
If anyone in western capitals had been hoping to see any sign of a leader diminished by 12 months of a full-scale and costly war in Ukraine, they would have been disappointed.
Instead, the Russian leader vowed to crank up the "mass production" of weapons and ammunition to keep his war machine alive.
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His language should harden the resolve of NATO allies as they consider their new posture in the wake of the war in Ukraine.
Jens Stoltenberg, the secretary general of NATO, has warned European member states in particular that they are in a "race of logistics" against Russia, given the vital need of western partners to keep supplying Ukraine's military with the munitions to fight.
But analysts have warned that many European states, including the UK, have yet to put their industrial base on to more of a war footing.
In the most significant announcement of his address, Mr Putin once again spoke about nuclear weapons - atomic sabre-rattling that has formed a central part of his efforts to deter the West from involvement in the Ukraine war.
In a televised speech to Russia's political and military elite, he said the Kremlin would pause its involvement in the New START Treaty - a landmark pact signed between then US president Barack Obama and then Russian president Dmitry Medvedev in Prague in 2010.
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The document, which had been due to expire in 2026, caps the number of deployed nuclear warhead both countries can deploy.
It had formed a central part of efforts by Washington to reset relations with Moscow during Mr Obama's time in power - a move that was short-lived given Mr Putin subsequently invaded Ukraine for the first time four years later with the illegal annexation of Crimea.
"I am forced to announce today that Russia is suspending its participation in the Strategic Arms Reduction Treaty [START]," Mr Putin said.
He claimed, without citing evidence, that some in the United States were thinking about resuming nuclear testing and warned that Russia would do the same if necessary.
"Of course, we will not do this first. But if the United States conducts tests, then we will. No one should have dangerous illusions that global strategic parity can be destroyed."
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Washington and Moscow have vast stockpiles of nuclear weapons left over from the Cold War and remain, by far, the biggest nuclear powers.
Between them, they hold 90% of the world's nuclear warheads.
Under the terms of the New START Treaty, the two countries may deploy no more than 1,550 strategic nuclear warheads and 700 land-based and submarine-based missiles and bombers to deliver them.
The United States called the Russian president's comment irresponsible but there was also confusion about what they actually meant in practice.
"It may have just been a talking point, or it may have signalled an intention to back away from the treaty in more substantive ways," said a US official who spoke on condition of anonymity and was quoted by the Reuters news agency.
Either way, the confrontational language from the very top of the Kremlin points to even greater hostilities between Russia and the West this year.