Vladimir Putin has said Russia will suspend its last remaining nuclear weapons treaty with the US, a move western officials said spelt the end of the post-cold war arms control regime.

In a state-of-the-nation address ahead of the first anniversary of his invasion of Ukraine, the Russian president said Moscow would freeze its participation in the New Start agreement with Washington.

The 2010 treaty limits the number of the two countries’ deployed strategic nuclear weapons and imposes an inspection and notification regime.

“Our relations have degraded and that’s completely and utterly the US’s fault,” Putin said, in his long-delayed speech to Russia’s political elite, insisting that Washington had in effect forced him to start the war by threatening Russia.

Hours before US president Joe Biden was set to give his own set piece address in Poland, after paying a surprise visit to Kyiv on Monday, Putin accused the “western elite” of seeking “to finish us off once and for all”.

US secretary of state Antony Blinken said the Russian leader’s decision to suspend participation in the New Start arms control deal was “deeply unfortunate and irresponsible”, while other western officials were more outspoken about its long-term consequences.

“With today’s decision on New Start, the whole arms control architecture has been dismantled,” said Nato secretary-general Jens Stoltenberg.

“More nuclear weapons and less arms control makes the world more dangerous.”

Josep Borrell, the EU’s chief diplomat, added that Putin’s decision was “demolishing the security system that was built after the end of the cold war”.

The US had said in January that Russia was failing to comply with the treaty after a breakdown in talks on resuming nuclear weapons inspections, halted during the height of the Covid-19 pandemic.

But Russia’s suspension of the treaty means it will no longer share information with the US about its nuclear arsenal and casts into still greater doubt whether the agreement, due to expire in 2026, will be renewed.

“We learned to live without inspections during the pandemic. But the hundreds of notifications exchanged are what prevent . . . miscalculation, misinterpretation, and misunderstanding,” said Samuel Charap, a senior political scientist at the Rand Corporation.

“This is very problematic — it was the last guardrail remaining in this domain,” he added.

Russia has said talks on the treaty are unlikely to resume unless the west agrees to hold comprehensive negotiations on Ukraine without Kyiv’s participation, which the US has said is unacceptable.

Putin also hinted at resuming nuclear tests, though he claimed Russia would only do so in response to the US.

“If the US conducts tests, then so will we. Nobody should have any illusions that global strategic parity can be destroyed,” the Russian president said. But he steered clear of repeating earlier veiled threats to use nuclear weapons against the west or Ukraine to defend Russia.

“Putin really thinks Russia is at war with the west and the US, and Ukraine is just one episode in this confrontation”, said Tatiana Stanovaya, a senior fellow at the Carnegie Endowment for International Peace. “Why give the US access to Russian nuclear sites, as the treaty holds, if they are at war with Russia?”

Putin’s speech was intended to demonstrate Moscow’s resolve, despite the failure of its initial blitzkrieg plan in Ukraine and the devastating losses Russia has suffered. “This is about the very existence of our country,” Putin said. Referring to the west he added: “They’re the ones who started the war. We are using force to stop it.”

Russia barred foreigners from attending, instead inviting military veterans and pro-Kremlin youth activists to sit alongside Russia’s political elite.

“The longer-range the western systems supplied to Ukraine are, the further we will be forced to push the threat away from our borders,” Putin said, in a reference to growing supplies of advanced weaponry to Kyiv.

The Kremlin had postponed the address, Putin’s first in nearly two years, and cancelled his annual end-of-year press conference after his attempted annexation of four Ukrainian provinces partly under Russia’s control backfired disastrously last year.

In an apparent acknowledgment of his country’s huge casualties, which the UK says could reach 200,000 men, Putin said Russia would set up a state foundation to support war veterans and their families.

But he maintained that Russia’s economy, which contracted by just 2.1 per cent this year despite western attempts to cut it off from global markets, had weathered the worst of sanctions.

He repeated a previous call, first made almost a decade ago, to “de-offshorise” Russia’s business elite by forcing them to register their foreign assets in Russian jurisdictions.

“No ordinary citizens felt sorry for those who lost their foreign assets and invested in yachts and palaces,” Putin said.

Many of Russia’s top officials and state company executives at the speech privately oppose the war, but have stayed in their posts and made their peace with it rather than speak out against Putin.

Putin insisted that Russia’s people were united in support of the war. He quoted the early 20th century Tsarist official Pyotr Stolypin’s invocation of “Russia’s one historical, higher right — the right to be strong”.