This video grab taken from handout footage posted on June 24, 2023, on the Telegram channel @razgruzka_vagnera shows Wagner boss Yevgeny Prigozhin (C) walking in the city of Rostov-on-Don

Washington (AFP) - The United States and its allies held close consultations but publicly stayed on the sidelines Saturday as officials waited to see how the armed revolt by longtime Kremlin insider Yevgeny Prigozhin and his private Wagner army would play out.

As the rebel force threatened to march on Moscow – then announced a stunning pull-back – US officials carefully avoided direct comment on what some stressed was an “internal” situation in Russia, while Moscow warned them to stay out of the fray.

US President Joe Biden spoke with the leaders of France, Germany and Britain amid concerns that Russian President Vladimir Putin’s control over the nuclear-armed country could be slipping.

A White House readout of their call said they discussed “the situation in Russia,” which erupted Friday after Prigozhin announced a challenge to the Russian Defense Ministry, seized control of the southern city of Rostov-on-Don and sent an armed column toward Moscow – before announcing his surprise about-face Saturday.

Defense Secretary Lloyd Austin also spoke with his Canadian, French, German, British and Polish counterparts, according to his spokesman.

The Chairman of the Joint Chiefs of Staff, General Mark Milley, cancelled a planned trip to Israel and Jordan, a sign of the serious concern in the US capital.

US Secretary of State Antony Blinken held a call with counterparts from Western Europe and Japan, with the partners pledging to “stay in close coordination,” said State Department spokesman Matt Miller after the call.

European Union foreign affairs chief Josep Borrell avoided direct comment on what he called an “internal” Russian issue.

But he said he had activated the EU crisis response center and was coordinating officials in the bloc ahead of a Monday meeting of the EU Foreign Affairs Council.

“Our support to Ukraine continues unabated,” he added.

- A ‘gift’ for Ukraine -

US President Joe Biden was briefed on the situation in Russia, the White House said

But beyond that, officials were mum, though clearly watching to see what would happen in Russia’s most serious security crisis in decades.

Biden and Vice President Kamala Harris met with top US security officials early Saturday on the Moscow crisis, including Austin, Milley, Director of National Intelligence Avril Haines and CIA Director William Burns.

A US military source said American officials need to be careful about what they say, noting that they do not want to give Putin or others any reason to cast blame for the situation on Washington.

Moscow issued a stiff warning to the US and allies to stay back.

“The rebellion plays into the hands of Russia’s external enemies,” the foreign ministry said in a statement.

“We warn the Western countries against any hint of possible use of the domestic Russian situation to achieve their Russophobic goals,” it said.

Moscow’s ally Belarus, meanwhile, called the uprising a “gift” to the West.

It was a sentiment echoed by Kyiv, where Deputy Defense Minister Ganna Malyar called the rebellion “a window of opportunity” for Ukraine’s armed forces.

Analysts agreed, with James Nixey, a Russia expert at the London-based Chatham House think tank, telling AFP that Ukraine would likely try to capitalize on the situation.

- Nuclear weapons -

A member of Wagner group sits atop of a tank in Rostov-on-Don, a Russian city which the private military group captured on June 24, 2023

Western allies were also looking to see if the turmoil inside Russia would offer any advantages for Ukraine as it pushes on in its counteroffensive against invading Russian forces in the east and south of the country.

A key concern, according to experts, is if Prigozhin’s rebel forces seek to gain control of any of Russia’s nuclear armory, particularly tactical nuclear weapons.

“This is an emerging danger and is exactly what policymakers most fear, a loose-nuke scenario,” wrote Alexander Vindman, a former White House National Security Council expert on Russia and Eastern Europe.

“This fear has plagued US policymakers since the collapse of the Soviet Union,” he said.

The White House did not respond when asked if there had been any communications with Moscow over the security of its nuclear weaponry.

Nixey said while things remain in flux, the West should not look to Prigozhin as a hero or count on the Russian elite turning away from Putin, and toward him.

Privately many Russians might consider Putin’s war on Ukraine as a “dreadful mistake,” he said.

But “that doesn’t translate into supporting Prigozhin, because of his maverick nature,” Nixey told AFP.

As for Kyiv, he said Prigozhin’s revolt does not mean an end to their fight.

“Whilst this is a useful distraction for the Ukrainians right now – and they will be pleased that this has happened and they will be looking to exploit it on the front line – he is not their knight in shining armor.”