Zelenskyy government: What happens if Kyiv falls? What would a government in exile look like?

As Russia's military pounds Ukraine, causing death and destruction, it has not yet seized the nation's capital, Kyiv.

Ukrainian President Volodymyr Zelenskyy, who says he's the Kremlin's No. 1 target, has vowed to stay in Ukraine, even as Russian troops bear down on Kyiv.

"According to our information, the enemy marked me as target No. 1, my family, as target No. 2,” Zelenskyy said in a video statement Thursday. “They want to destroy Ukraine politically by destroying the head of state. We have information that enemy sabotage groups have entered Kyiv.”

Zelenskyy’s whereabouts are under wraps after he told European leaders in a call Thursday that they might not see him again alive. But he said he will be staying in the capital.

On Friday, Zelenskyy posted a short video proclaiming Ukraine's continued defense against the Russian invasion. His defiance came even as questions swirled on social media about whether leaders had begun fleeing.

“We are all here,” said Zelenskyy, who was surrounded by a handful of leaders. “Our military is here, citizens are here. We are all here defending our independence, our state and it will be so further. Glory to our defenders, glory to Ukraine!"

Zelenskky also spoke with President Joe Biden for 40 minutes on Friday about strengthening sanctions against Russia and other steps to retaliate for Russia’s invasion of Ukraine. A few hours later, the Biden administration announced that it will join the European Union in imposing fresh sanctions against Russian President Vladimir Putin and some of his deputies in retaliation for the attack on Ukraine.

Putin ordered an invasion of the neighboring country, an assault that began in eastern Europe's pre-dawn hours on Thursday.

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Here is what it would mean for Zelenskyy if Russia seized Kyiv:

What happens if Kyiv falls?

Zelenskyy has repeatedly voiced his intention to stay, even at one point saying during an address on Thursday that when Russians attack Ukrainians “you will see our faces, not our backs, but our faces.”

But experts say that if Kyiv fell to Russian forces that Zelenskyy would either be killed or become a prisoner of Russia. If he were to escape, he could set up operations in western Ukraine.

Zelenskyy could run the government from western Ukraine if he has proper communications set up and continued resistance from Ukrainian forces on the ground fighting Russia, said John Herbst, senior director of the Eurasia Center for the Atlantic Council and a former U.S. ambassador to Ukraine from 2003 to 2006.

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“What we're looking for is there going to be a resistance that can persist and that Russia cannot stamp out,” Herbst said.

With Zelenskyy out of Kyiv, Putin would likely put in place his hand-selected government, said Mitchell Orenstein, professor of Russian and East European Studies at the University of Pennsylvania.

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Orenstein, author of "The Lands in Between: Russia vs. the West and the New Politics of Hybrid War," said Putin would put in place an oppressive government that would rule in a “brutal fashion” like the Luhansk People's Republic, which is a self-proclaimed breakaway state located within Ukraine and a designated terrorist organization.

“The whole prospect of Russia running Ukraine I doubt is going to work as smoothly as Putin might expect, whether it's by a proxy government or by a Russian government, just because there's a lot of animosity between patriotic Ukrainians and those that Putin might select for the job,” Orenstein said.

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What would a government in exile look like?

If Zelenskyy fled Ukraine, he would likely become a leader in exile.

There have been several cases in which a country’s government has had to function in exile. During World War II, the Polish government resided in London after the invasion by Nazi Germany and the Soviet Union. The Rada of the Belarusian Democratic Republic is another example of a government in exile.

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A major dilemma with governments in exile is whether they will be treated as legitimate over the government that is put in place of the country they are representing, said Paul D’Anieri, professor of political science and public policy at the University of California, Riverside.

With the Polish government was in exile, for example, “there was a real dilemma for outside actors as to whether you deal with a government that's declared to be the government but doesn't really control anything versus a government who is actually in control in a country, even if you think that they're evil and they came to power illegally," D’Anieri said.

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Herbst said if Zelenskyy leads a government-in-exile, it would “be a defeat for Ukraine, but not necessarily an end to the war.” 

“The absolute key question is whether Ukrainian resistance to the Russian invasion continues and in some sense, stabilizes,” he said, adding that in the next several weeks “Russia will make gains, but do those gains mean an end to effective resistance?”

Herbst said resistance from Ukraine's military and its citizens are going to be Putin’s big problem going forward, regardless of whether Zelenskyy’s government is toppled or decides to depart.

“This is a real problem for Putin. He needs to win relatively fast,” he said. “And if four months from now Ukrainians are still resisting, Putin has got a big, big problem.”

Contributing: Michael Collins and Bart Jansen

Reach Rebecca Morin at Twitter @RebeccaMorin_

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