Ukrainian President Volodymyr Zelensky said on Friday that his chief of staff, Andriy Yermak, has submitted his resignation amid a corruption scandal.
Ukrainian anti-corruption agencies searched Yermak's home, escalating a major political crisis as Kyiv faces pressure from Washington to accept terms for a peace deal. Yermak said he was fully cooperating with the investigators.
Yermak confirmed that his apartment was being searched and said he was fully cooperating with the investigators.
Yermak leads Kyiv's negotiating team, trying to hash out terms after Washington presented a draft backing Russian demands.
The National Anti-Corruption Bureau of Ukraine and the Specialised Anti-Corruption Prosecutor's Office said jointly that the searches were "authorized" and linked to an unspecified investigation.
Earlier this month, the two anti-graft agencies unveiled a sweeping investigation into an alleged $100 million kickback scheme at the state atomic energy company that ensnared former senior officials and an ex-business partner of Zelensky.
Searches could inflame political tensions
Yermak, 54, had been a close friend of Zelensky since before the one-time sitcom star embarked on his political career, and helped guide his 2019 presidential campaign.
He has not been named a suspect, but opposition lawmakers and some members of Zelensky's own party earlier called for his dismissal as part of Ukraine's worst wartime political crisis.
Friday's searches are likely to inflame tensions between Zelensky and his political opponents as Kyiv faces mounting pressure to accept a deal that could force it into painful concessions.
In a statement earlier on Friday, the opposition European Solidarity party called for Yermak's dismissal and his removal from the negotiating team, as well as for a new coalition government and talks with Zelensky.
"The issue of peace and the fate of Ukrainians cannot depend on the personal vulnerabilities and tarnished reputation of politicians involved in a corruption scandal," it said.
Yermak's position in question
The US-backed peace push comes as Russian forces grind forward along several parts of the sprawling front line. Moscow says its troops are close to capturing the eastern city of Pokrovsk, which would be their biggest prize in nearly two years.
On Thursday, Russian President Vladimir Putin said a 28-point US peace plan leaked last week could be "a basis for future agreements." He demanded Kyiv withdraw troops from the eastern land it holds before Moscow stops fighting.
Speaking to The Atlantic magazine this week, Yermak said, "no one should count on us giving up territory."
Oleksandr Merezhko, a lawmaker from Zelensky's party who serves as head of the parliamentary foreign affairs committee, told Ukrainian outlet Glavkom the scandal could have a negative impact on talks.
Another pro-Zelensky lawmaker, Bohdan Yeremenko, went further, writing on Facebook that it would be "impossible to save" Yermak.
"There is no such friendship that would be worth a good name," he said.
Kyiv's partners watching closely
Showing progress in fighting corruption is a central element of Kyiv's bid for European Union membership, which Ukrainian officials see as critical to breaking out of Russia's orbit.
In a statement, a European Commission spokesperson said Brussels "will continue to follow the situation closely."
The two anti-graft agencies have stepped up their campaign during Russia's invasion, but have said they face pressure from vested interests.
Zelensky briefly rolled back their independence last July but reversed course after a public outcry and criticism from foreign partners.