Ukrainian authorities made accusations of money laundering and fraud against billionaire oligarch Igor Kolomoysky, the owner of a media holding, through which President Volodymyr Zelensky made his rise to fame as a comedian and later as a presidential candidate.

The Security Service of Ukraine (SBU) said in a statement on Saturday that Kolomoysky laundered, between 2013 and 2020, over 500 million in Ukrainian currency ($13.5 million) by "transferring it abroad, while using the infrastructure of banking institutions controlled by him," describing him as the "de facto owner of a large financial and industrial group."

The powerful businessman, who holds a Cypriot citizenship and an Israeli passport, was handed a "notice of suspicion" on charges of fraud and laundry of property obtained by criminal means.

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Zelensky announced his presidential candidacy in 2019 through Kolomoysky-controlled TV channel 1+1, the same channel that aired the President's comedy show "Servant of the People" in 2015 and offered him a platform to promote his campaign.

But Zelensky has denied having personal ties to the businessman, describing their relationship as strictly professional.

"Unsurprisingly, many viewed Zelenskyy as Kolomoisky’s candidate," US-based think tank the Atlantic Council said in 2021.

The crackdown on Kolomoysky began earlier in February, when he became a suspect in an embezzlement case of 40 billion hryvnia ($1.1 billion), as well as tax evasion through his oil businesses.

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His entry into politics started in 2014 after he became affiliated with the Western-backed colored revolution, known as the Maidan Coup, among other names.

Kolomoysky subsequently served as the governor of Ukraine's southeastern Dnepropetrovsk Region but faced dismissal when he initiated a campaign to privatize two state-owned energy companies.

Additionally, he was the owner of Ukraine's largest bank, PrivatBank, until the government nationalized it in 2016, citing allegations of large-scale fraud that posed a significant threat to the country's financial system, according to Kiev then.

In 2021, the United States imposed sanctions on the oligarch and his family members for his involvement "in corrupt acts that undermined rule of law and the Ukrainian public’s faith in their government’s democratic institutions."

Kolomoysky has denied Kiev's accusations.