Former US ambassador Joe Hockey says there is now a 30pc chance Vladimir Putin will use nuclear weapons on Ukraine

Joe Hockey backs warnings of a potential nuclear Armageddon, revealing details of private conversations that have him fearful of devastating strikes.

A Ukrainian soldier observes as a 2S1 Gvozdika self-propelled howitzer fires on the front line in the eastern Donetsk region this week. Picture: AFP

Joe Hockey has backed Joe Biden’s warning of potential “nuclear Armageddon”, putting at 30 per cent the chance Russian president Vladimir Putin would use tactical nuclear weapons in the coming months in a bid to regain the initiative in his failing effort to subdue Ukraine.

A week after US President Joe Biden’s stark warning about the risk of cataclysmic nuclear war, the former treasurer and ambassador to the US said his private conversations with leaders in London and Washington had led him to believe the chance of at least limited nuclear war was almost one third.

“There is now a 30 per cent chance Vladimir Putin will deploy limited nuclear weapons in an attempt to consolidate the Russian position in Ukraine,” Mr Hockey wrote in a note to clients of Bondi Partners, Mr Hockey’s private advisory firm, on Monday (Tuesday AEDT).

“There is no bigger risk to world peace and the global economy than what is unfolding in Ukraine at the moment. We are on the precipice of a significant moment in modern history”.

Mr Hockey said Vladimir Putin’s advancing age, in a nation where life expectancy was 66, increased the likelihood Russia would deploy some of its massive arsenal of almost 2,000 tactical nuclear warheads, which could be deployed by “a single turn of a key in a battlefield situation”.

“His health is not what it was. … you don’t need to be a genius to work out that he is capable and willing to use limited nuclear weapons if (the) Ukrainian war continues on its current path,” Mr Hockey wrote, adding a silver lining that Russia’s military industrial complex was so corrupt the weapons may not work.

“Estimates of corruption are so high in the Russian military that up to 80 per cent of Russia’s assumed high end technology is ineffective; this has gutted the capability of the Russians and, if widely known in Russia, would lead to significant civil unrest”.

Joe Hockey, former Australian ambassador to the US, stands in front of Capitol Hill in Washington. Picture: Allison Shelley

Mr Hockey’s warning came as top US officials played down the likelihood of a nuclear escalation, days after Russia launched a wave of missile strikes on multiple Ukrainian cities, killing and wounding over 100 civilians, as reprisal for alleged Ukrainian attack on Russia’s Kerch Strait Bridge.

In a press briefing on Tuesday (Wednesday AEDT), White House national security spokesman John Kirby said the US was closely watching Russia’s nuclear arsenal “as best we can”, promising Washington would shortly send more advanced missile defence systems to Ukraine and leaving open the door for provision of F-16 aircraft.

“We’ve seen no indication the Russian apparatus is moving to prepare for (a nuclear) decision. We have seen nothing to cause us to change our own strategic deterrence posture,” Mr Kirby said.

Mr Putin has repeatedly, throughout Russia’s eight-month long invasion of Ukraine, warned NATO that Moscow would not hesitate to use nuclear weapons if it believed its “territorial integrity” was at stake, a threat that became a greater concern after Russia formally annexed four eastern regions of Ukraine.

A destroyed apartment in the town of Bakhmut in the Donetsk region. Picture: AFP

Mr Kirby declined to comment on reports Elon Musk, the world’s richest man and Tesla co-founder, had telephoned the Russian president before Mr Musk’s controversial proposal last week of potential peace terms between the two warning nations, including acknowledging Crimea as Russian.

“Mr Zelensky will get to determine for himself when is the right time to negotiate, and Mr Zelensky will get to determine for himself and his country what terms he’s willing to consider, we are not going to dictate those,” Mr Kirby said.

Mr Musk has since denied the phone call allegation, tweeting that he only spoke to Mr Putin 18 months ago “about space”.

In a separate statement on Tuesday G7 leaders, following a phone call with Ukrainian president Volodymyr Zelensky, said they would continue to provide financial, humanitarian, military, diplomatic and legal support “for as long as it takes”, condemning neighbouring Belarus for accommodating Russian troops.

“The announcement of a joint military group with Russia constitutes the most recent example of the Belarusian regime’s complicity with Russia,” the statement said.

A man examines a destroyed car destroyed by a missile strike in a residential area near Tower 101, not far from Kyiv's main train station. Picture: Getty Images

Mr Kirby also revealed the US would review its relationship with Saudi Arabia after it orchestrated a two million barrel a day cut in OPEC’s oil production, announced last week, in what appeared to be a bid to help Russia and hamper Democrats’ chances – by pushing up petrol prices – in looming midterm elections.

“The President believes we need to … see if that relationship is where it needs to be … if it’s serving our national security interests,” he said, an announcement that followed calls from Democrat politicians to wind back US military and other support for the oil-rich kingdom, in which US troops have long been stationed.

In his period note to clients, Mr Hockey also predicted China’s president Xi Jinping’s grip on the Chinese Communist Party was loosening, foreshadowing turmoil in Beijing as Mr Xi sought election for another five-year term at the upcoming 20th National Congress of the CCP.

“I have much more confidence in the next 12 months that King Charles’s coronation will proceed more smoothly than President Xi’s coronation beginning October 16,” he wrote.

“Significant upheaval is not a remote possibility”.