Defying all expectations, Ukrainian President Volodymyr Zelenskyy has bravely led his nation in a fierce resistance against Russia’s unprovoked military aggression.  

Zelenskyy has remained defiant, declaring to Russia and the world that he is staying put, providing a much-needed morale boost to his troops and citizens as they face invasion from one of the world's largest militaries. 

Volodymyr Zelenskyy

In this photo, Feb. 27, 2022, taken from video provided by the Ukrainian Presidential Press Office, Ukrainian President Volodymyr Zelenskyy speaks to the nation in Kyiv, Ukraine.   (Ukrainian Presidential Press Office via AP)

"Not hiding, and I’m not afraid of anyone," Zelensky said in a social media post Monday evening from his presidential offices in Kyiv.  

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Still, questions linger about Ukraine’s fate if something were to happen to Zelenskyy, who has reportedly survived three assassination attempts. Who, for instance, would take Zelenskyy’s place, and what would it mean for Ukraine’s fight against Russia? 

U.S. Secretary of State Anthony Blinken confirmed to CBS News’ Face the Nation on Sunday that Ukraine’s government has a contingency plan in place if Zelenskyy is killed. 

"The Ukrainians have plans in place – that I’m not going to talk about or get into any details on – to make sure that there is what we would call ‘continuity of government’ one way or another," Blinken said, without providing further details. 

In this March 8, 2022, image from video provided by the Ukrainian Presidential Press Office and posted on Instagram, Ukrainian President Volodymyr Zelenskyy speaks in Kyiv, Ukraine. (Ukrainian Presidential Press Office via AP)

In this March 8, 2022, image from video provided by the Ukrainian Presidential Press Office and posted on Instagram, Ukrainian President Volodymyr Zelenskyy speaks in Kyiv, Ukraine.  (Ukrainian Presidential Press Office via AP)

The Ukrainian Constitution outlines that the speaker of the parliament succeeds the president if anything were to happen to them in office. However, the succession line beyond speaker of the parliament remains unclear. Complicating matters further is that Ukrainian officials have not publicly discussed succession, saying they want to focus on fighting. 

Here is a look at some of Ukraine’s top leaders: 

Ruslan Stefanchuk, Ukraine’s Speaker of Verkhovna Rada

Ruslan Stefanchuk, 46, is the Chairman, or Speaker, of the Verkhovna Rada, Ukraine’s parliament, a position he has held since October 2021. Before that, Stefanchuk was Zelensky’s representative in the Rada. 

Ukraine Parliament Speaker Ruslan Stefanchuk

Newly appointed Parliament Speaker Ruslan Stefanchuk, a lawmaker from the ruling Servant of the People party, reacts during a session of parliament in Kyiv, Ukraine October 8, 2021. (REUTERS/Valentyn Ogirenko)

The New York Times described Stefanchuk as a "pro-Western politician and former top aide to Mr. Zelenskyy." 

Denys Shmyhal, Ukrainian Prime Minister

Denys Shmyhal, 46, has served as the Ukrainian Prime Minister since March 2020. His previous positions in government included Deputy Prime Minister – Minister Development and Territories of Ukraine and Governor of Ivano-Frankivsk Oblast in Western Ukraine. 

Prime Minister of Ukraine Denys Shmyhal, right, stands with Ruslan Stefanchuk, left, and Ukraine President Volodymyr Zelenskyy as he signs an application for the membership of Ukraine in the European Union on Monday Feb 28, 2022.

Prime Minister of Ukraine Denys Shmyhal, right, stands with Ruslan Stefanchuk, left, and Ukraine President Volodymyr Zelenskyy as he signs an application for the membership of Ukraine in the European Union on Monday Feb 28, 2022. (Ukraine Presidential Office/EYEPRESS)

Former Ukrainian Prime Minister Oleksiy Honcharuk previously described Shmyhal as "an excellent manager." 

As prime minister, Shmyhal was responsible for overseeing the Ukrainian government’s response to the COVID-19 pandemic.   

Dmytro Kuleba, Ukrainian Foreign Minister 

Dmytro Kuleba, 40, has served as Ukraine’s Foreign Minister since March 2020. One of the youngest diplomats in Ukraine’s history, Kuleba in Ukraine’s foreign ministry for over a decade and worked to foster closer relations with Europe. 

Ukrainian Foreign Minister Dmytro Kuleba

Ukrainian Foreign Minister Dmytro Kuleba speaks during a joint press conference with Italian Foreign Minister following their meeting in Kyiv on February 15, 2022.  ( Sergey Dolzhenko/pool/AFP Via Getty Images)

Kuleba has appealed to the international business community to cease operations with Russia. In a recent op-ed for The Washington Post, Kuleba said "history will judge each one of us later on how we faced" the threat of Russia’s "hateful expansionism." 

"Ukraine will prevail – light will win over darkness, as President Volodymyr Zelensky said," Kuleba wrote. "We are holding our ground." 

Kuleba has also authored the book, "The War for Reality: How to Win in the World of Fakes, Truths, and Communities." 

Ukrainian President Volodymyr Zelenskyy's speech is streamed live on a big screen in front of Parliament during a rally in support of Ukraine on March 4, 2022, in Tbilisi, Georgia.

Ukrainian President Volodymyr Zelenskyy's speech is streamed live on a big screen in front of Parliament during a rally in support of Ukraine on March 4, 2022, in Tbilisi, Georgia.  (Photo by Daro Sulakauri/Getty Images)

Khrystyna Holynska, a professor of Public Policy at the Kyiv School of Economics, wrote in a piece for the Rand Corporation that Zelenskyy's cabinet is likely keeping its plans for continuity of government secret to reduce the risk of a government collapse. 

Zelenskyy vowed that Ukraine would fight Russia's invasion in its cities, fields and riverbanks. 

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"We will not give up and we will not lose," he told Britain's packed House of Commons via video, evoking the "never surrender" speech that Winston Churchill gave during the darkest days of World War II.