'Precipice of collapse': Putin's army facing 'irreversible' defeat, former U.S. generals say
Vladimir Putin. (Photo via AFP)

Former U.S. generals say Russian leader Vladimir Putin's army in Ukraine may be near "irreversible" defeat, according to comments they made on Sunday.

“No amount of shambolic mobilization, which is the only way to describe it, no amount of annexation, no amount of even veiled nuclear threats can actually get [Putin] out of this particular situation,” said retired Army General David Petraeus on ABC News on Sunday. “He is losing, and the battlefield reality he faces is, I think, irreversible.”

“The reality facing Russia now is that Ukraine, a country a third the size of Russia, has a bigger, much more effective army on the ground, and other assets as well,” Petraeus added. “He's already lost a really critical element in that, a critical city that would have been a very key supply hub had they been able to go farther. And that's just going to continue. He's going to continue to lose on the battlefield. And at some point, there's going to have to be recognition of that.”

Ukraine's liberation of the rail hub city Lyman arrived as Russian forces departed without a fight, following concerns they could be surrounded.

“This is a tremendous victory for the Ukrainians," retired Lieutenant General and former security advisor to former President Donald Trump H.R. McMaster told CBS. "And it's a victory that I think that they could turn into a cascading series of defeats of Russian forces."

"What we might be at here is really at the precipice of really the collapse of the Russian army in Ukraine," McMaster added, "a moral collapse.”

Last week, Russian President Vladimir Putin ordered a partial mobilization to reinforce his troops in Ukraine following major losses, after Ukraine retook vast stretches of its territory from invading Russian forces. In his announcement of the mobilization, Putin said Russia was threatened with "disintegration" by the Western powers backing the Ukrainian government.

He also warned NATO that nuclear-armed Russia could use any weapons in its armory against what he called Western "nuclear blackmail."

The announcement comes as Russia is believed to face shortages of manpower. The Russian president also hinted at the use of nuclear weapons when he said Russia will use “all the instruments at its proposal to counter a threat against its territorial integrity — this is not a bluff.”

The calling up of potentially 300,000 reservists would mark the largest Russian mobilization of troops since World War II “and all but ensures that there will be no near-term off-ramp for the military conflict, which has already left thousands dead and is imposing ruinous economic costs on Europe,” Helima Croft, head of global commodity strategy at RBC Capital Markets, wrote in a note.