President Volodymyr Zelenskiy stripped four political figures of their Ukrainian citizenship, including pro-Kremlin politician Viktor Medvedchuk who was transferred to Russia last year in a prisoner swap deal.
"I have decided to terminate the citizenship of four persons: Andriy Leonidovych Derkach, Taras Romanovych Kozak, Renat Raveliyovych Kuzmin and Viktor Volodymyrovych Medvedchuk," Zelenskiy said in his nightly video address.
"If people's deputies choose to serve not the people of Ukraine, but the murderers who came to Ukraine, our actions will be appropriate."
Medvedchuk, a close ally of Kremlin leader Vladimir Putin, headed a banned pro-Russian party the "Opposition Platform - For Life" in Ukraine and was facing treason charges before being transferred to Moscow in September 2022.
Kozak and Kuzmin had been both elected to Ukraine's parliament as members of Medvedchuk's party.
The United States imposed sanctions on Kozak, the owner of three television channels, in January of 2022 for alleged spreading of Russian disinformation, after Kyiv sought his arrest on treason charges.
Ukraine has also charged Kuzmin with high treason.
Derkach, a Ukrainian lawmaker also sanctioned by Washington, was charged in the United States in December with money laundering and sanctions violations.
He had been accused of helping Russia interfere in the U.S. presidential election in 2020.
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