Eastern Ukraine — The U.N. Security Council held a meeting on Monday — called by the U.S. and over Russia's objection — to discuss the, along which Russia has massed more than 100,000 troops. The U.S. and its NATO allies have warned for weeks that President Vladimir Putin could use the forces to launch a new invasion of Ukraine as soon as February, though Putin's government denies any such intentions.
The U.S. has responded by pouring military hardware in to bolster Ukraine's forces, and NATO has deployed troops, aircraft and warships to reinforce the bloc's defenses in the region. The U.S. and its European allies won't send troops into Ukraine as it's not a NATO member, but they've warned repeatedly that any Russian forces crossing the Ukrainian border will be considered an invasion, and will draw prompt and severe sanctions against Russia.
As CBS News senior foreign correspondent Holly Williams reports, Ukrainians are determined to defend their homeland, but even with an influx of American weaponry, they're massively outgunned and outnumbered by their colossal neighbor.
Despite the odds, thousands of Ukrainian civilians have joined local defense units. Williams met some of the citizen soldiers on the outskirts of Ukraine's capital where, every Saturday, they gather and do a quick warm up before they're put through drills — training to help fight off a hypothetical Russian attack.
"I know Russians very well," Oleksei Vasilchenko told Williams. The defense unit volunteer works in marketing, but told CBS News he served in the Soviet army before Ukraine gained its independence from Moscow just over 30 years ago.
"If you want peace, you should be prepared for war," he said.
The defense unit volunteers include everyone from urban professionals to military veterans like Vasilchenko, to new recruits. Many are thus far armed only with plywood rifles — stand-ins for the real thing.
Russia's hardware, on the other hand, is impressive — and Moscow has been showing it off. Putin's forces have moved fighter jets, missile systems and about 5,000 troops into Belarus, an ally and neighbor that sits on Ukraine's northern border.
Russia insists that it is merely carrying out joint military exercises there, and that there's no plan to invade Ukraine. But on Monday, the Russian military noted that the exercises were expanding with the establishment of "mobile field command posts" in Belarus. The lack of Russian command and control centers set up in the border region has been one factor noted by military analysts to suggest that Moscow is not, in fact, planning an imminent invasion.
U.S. Ambassador to the U.N. Linda Thomas-Greenfield told the Security Council members on Monday that the U.S. had "seen evidence that Russia intends to expand that presence [in Belarus] to more than 30,000 troops near the Belarus-Ukraine border, less than two hours north of Kyiv, by early February."
"If Russia further invades Ukraine, none of us will be able to say we didn't see it coming," Thomas-Greenfield told the meeting, appealing to Russia to pursue a diplomatic path rather than further escalation.
Russia fired back during the meeting, accusing the U.S. and its allies of interference for criticizing Russia's military exercises and dismissing the suggestions of a possible invasion as "conjectures and unfounded accusations."
"Our Western colleagues talk about the need for de-escalation, but first of all they themselves escalate tension with rhetoric and provoke an escalation," Ambassador Vasily Nebenzya said. "Talking about an impending war is provocative in itself."
But the drills in Belarus aside, Russia has done nothing to explain why it decided to move so many forces close to its border with Ukraine over the last year in the first place. Russian officials have said for months that the deployments are merely for exercises, and that they can do what they want when they want on their own soil.
In what appeared to be a continuation of the mixed messages coming from Moscow, even as it announced the command posts being set up in Belarus, the Russian military also said on Monday that some 6,000 troops deployed to the west of the country weeks ago, for "planned operational and combat training," had been moved back to their permanent bases.
Back in the forest outside Ukraine's capital of Kyiv, the local defense unit's members remained just as uncertain about Putin's intentions as the rest of the world. But they're also determined to be ready. CBS News watched as they kept up their fitness and practiced for the possibility of urban warfare.
"Everywhere here is our land, so we have to defend it," said volunteer Oleksei Ilyushan, who's a criminal lawyer during the work week. "It makes me angry, but it's not like, 'Aargh, What am I gonna do?' — It makes me angry like, to prepare myself, you know?"
The U.S. has said a Russian invasion of Ukraine would be horrific and change the world, but the Biden administration has also said there's still time for President Putin to choose de-escalation.
Putin is still formulating his official response to proposals from Washington that were handed over last week as a reply to Russia's demands for "security guarantees from NATO. Moscow demanded that NATO pull its forces back from Russian border regions and reject any new bids for membership from former Soviet states — most importantly, Ukraine.
The U.S. and NATO made it clear that they would not bar any prospective new members on Russia's behalf, but they have indicated a willingness to negotiate on military exercises and weapons deployments in the region, in addition to other "trust building" actions that both sides might take to step back from the brink of war.
Putin's spokesman said Monday that the Russian leader would give his reply "as soon as he deems it necessary."
In the meantime, the U.S. and its allies were sure to try to use the public forum of a U.N. Security Council meeting on Monday to increase the pressure on Moscow.
The next day, Russia's Foreign Minister Sergey Lavrov was to hold a phone call with his U.S. counterpart, Secretary of State Antony Blinken, according to the Russian ministry.
Britain's foreign and defense ministers were also expected to visit Russia next week, Moscow's ambassador in London told a Russian television station on Monday, as efforts to find a diplomatic solution to the crisis gained urgency.
CBS News' Pamela Falk at U.N. Headquarters contributed to this report.
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