Ukrainian President Volodymyr Zelenskyy says his chief of staff, Andriy Yermak, has resigned, as a major corruption investigation continues to roil Kyiv and cause consternation among its allies.

Zelenskyy’s announcement on Friday came just hours after anticorruption authorities searched Yermak’s home.

“The Office of the President of Ukraine will be reorganised. The head of the office, Andriy Yermak, has submitted his resignation,” the Ukrainian president said in a video address, adding he would hold consultations with a possible replacement on Saturday.

Yermak, who had been leading the Ukrainian team trying to negotiate a United States-proposed plan to end Kyiv’s four-year war with Russia, had confirmed his apartment was being searched earlier in the day and said he was fully cooperating.

“There are no obstacles for the investigators. They have been given full access to the apartment, and my lawyers are present on-site, cooperating with the law enforcement officers. From my side, there is full cooperation,” he wrote on social media.

Yermak did not immediately comment on the resignation announcement from Zelenskyy.

In a joint statement, the National Anti-Corruption Bureau of Ukraine and the Specialised Anti-Corruption Prosecutor’s Office had said the searches were “authorised” and linked to an unspecified investigation.

Earlier this month, the two anticorruption agencies unveiled a sweeping investigation into an alleged $100m kickback scheme at the state atomic energy company that ensnared former senior officials and an ex-business partner of Zelenskyy.

Friday’s searches came as the Ukrainian president faces growing pressure from the administration of United States President Donald Trump to agree to its proposal to end the war.

Ukraine and its European allies had raised concerns that the Trump-backed plan comprised some elements that Russia has been actively pushing for, including that Ukraine cede additional territory and curtail the size of its military.

But a revised proposal has been put forward, and Kyiv has said it is open to negotiations.

Zelenskyy has also faced pressure from his political opponents, with the opposition European Solidarity party earlier this week criticising Yermak’s role as a negotiator and calling on the Ukrainian president for “an honest dialogue” with other parties.

In his video address announcing Yermak’s resignation on Friday, Zelenskyy appealed for national unity amid the crisis.

“Russia very much wants Ukraine to make mistakes,” he said. “There will be no mistakes on our part. Our work continues.”

Key ally

Yermak, 54, has been Zelenskyy’s most important ally, but is a divisive figure in Kyiv, where his opponents say he has accumulated power, gatekeeps access to the president, and ruthlessly sidelines critical voices.

A former film producer and copyright lawyer, Yermak came into politics with Zelenskyy in 2019, previously working with him during the now-president’s time as a popular comedian.

He has been widely considered the second-most influential man in the country and even sometimes nicknamed “vice president”.

“Andriy Yermak is basically as close as you can get to President Zelenskyy without being President Zelenskyy himself,” Al Jazeera’s Rory Challands reported from Kyiv on Friday.

He noted that Yermak was dispatched by Zelenskyy this week to hold talks with senior US officials in Geneva, Switzerland, to try to redraft the Trump administration’s plan to end the war.

While Zelenskyy’s statement on Friday appeared to be trying to soften the blow Yermak’s resignation may have on his government, Challands said the impact on the Ukrainian president is “unmistakable”.

“This couldn’t be more critical for Ukraine at the moment,” he said. “It is negotiating its very survival as a sovereign nation.”

Meanwhile, the Ukrainian corruption investigation continues into an alleged scheme involving Energoatom, the state-run nuclear power company that supplies more than half of the country’s electricity.

Anticorruption investigators have said they suspect that Tymur Mindich, a one-time business partner of Zelenskyy, was the plot’s mastermind.