Defense Secretary Lloyd J. Austin III spoke with his Russian counterpart on Sunday for the second time in three days, U.S. officials said, in a conversation meant to delineate red lines that could potentially prompt Russia to launch a nuclear attack on Ukraine.
The conversation with Russian Defense Minister Sergei K. Shoigu at 7:30 a.m. EST was meant to clarify for the Biden administration why President Vladimir V. Putin is increasingly raising the specter of a nuclear strike in Ukraine, two officials said. With his forces on the back foot, Mr Putin has sought to paint the Ukrainian territory he has illegally annexed as part of “Mother Russia”, saying any US-backed attack in those areas would be seen as an attack on the Russian homeland. .
The Russian Defense Ministry confirmed that the two men spoke, saying only that they discussed the situation in Ukraine.
Mr. Austin and Mr. Shoigu spoke at the opening of the Pentagon on Friday. Before that, the last two spoke to each other in May.
A US official said on Sunday that Moscow’s reliance on Iranian drones, coupled with Mr Putin’s growing references to nuclear weapons, meant a desperate Russia was looking for other tools to use in its arsenal. Mr Putin’s forces have faced battlefield struggles in Ukraine and there is growing concern at home about the way his military is handling the war.
The conversation with Mr Austin was part of a flurry of calls Mr Shoigu had with other senior defense officials on Sunday. In talks with his British, French and Turkish counterparts, Mr Shoigu raised concerns that Ukraine could use a “dirty bomb”, according to the Russian Defense Ministry. Russia has not publicly offered any evidence to support its claims, and the allegations have drawn a swift and fierce response from Ukrainian and Western officials.
Ukrainian Foreign Minister Dmytro Kuleba called them “lies” that were “as absurd as they are dangerous”.
“We don’t have ‘dirty bombs’, and we don’t plan to acquire any,” he added. wrote on Twitter.
A so-called dirty bomb would use traditional explosives to pulverize radioactive material, and Russia has previously warned of the possibility that a bomb could be introduced into the war in Ukraine.
The White House called Mr Shoigu’s claims “obviously false”, while the Pentagon said Mr Austin “has rejected any pretense for Russian escalation”.
The British Ministry of Defense has also refuted these allegations.
So far, President Biden has tried to avoid escalating the nuclear crisis and has signaled that he still has no intention of directly involving US troops – or the US nuclear arsenal – in a war with Russia. At the same time, US officials say the US would be hard pressed not to react one way or another if Mr Putin used a nuclear weapon in the war in Ukraine.
Ukrainian President Volodymyr Zelensky has called for more support from the West given Mr Putin’s nuclear threats.
“When a terrorist state ups the ante, it has to feel like it won’t work,” he said in his evening speech.