Putin delivers nuclear warning to West over Ukraine, suspends START pact

President Vladimir Putin has delivered a nuclear warning to the West over Ukraine, suspending a bilateral nuclear arms control treaty and announcing new strategic systems had been put on combat duty.

Speaking nearly a year to the day since ordering an offensive that has triggered the biggest confrontation with the West since the depths of the Cold War, Putin warned on Tuesday that Moscow could resume nuclear tests.

"The elites of the West do not hide their purpose. But they also cannot fail to realise that it is impossible to defeat Russia on the battlefield," Putin told his country's political and military elite.

Cautioning the United States that it was stoking the war into a global conflict, Putin said that Russia was suspending participation in the New START Treaty, the last major arms control treaty between Moscow and Washington.

It limits the number of nuclear warheads the world's two biggest nuclear powers can deploy and is due to expire in 2026.

"I am forced to announce today that Russia is suspending its participation in the Strategic Arms Reduction Treaty," said Putin.

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Systems on combat duty

In his address, Putin claimed that some people in Washington were thinking about resuming nuclear testing and that he had information the US was developing new types of nuclear weapons.

Russia's defence ministry and nuclear corporation Rosatom should therefore be ready to test Russian nuclear weapons if necessary, he said.

"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," Putin said.

"A week ago, I signed a decree on putting new ground-based strategic systems on combat duty. Are they going to stick their nose in there too, or what?"

It was not immediately clear which ground-based systems had been put on combat duty. Putin said Ukraine had sought to strike a facility deep inside Russia where some of its nuclear bombers are based, a reference to the Engels air base.

Russia and the United States have vast arsenals of nuclear weapons left over from the Cold War and remain, by far, the biggest nuclear powers. Between them, they hold 90 percent of the world's nuclear warheads.

The New START Treaty limited both sides to 1,550 warheads on deployed intercontinental ballistic missiles, submarine ballistic missiles and heavy bombers. Both sides met the central limits by 2018.

The United States said in its 2022 Nuclear Posture Review that Russia and China were expanding and modernising their nuclear forces, and that Washington would pursue an approach based on arms control to head off costly arms races.

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