Ukraine’s president, Volodymyr Zelenskiy, has fired his prosecutor general amid a major reshuffle of his government this week. The move has alarmed anti-corruption activists and western governments, who fear it puts the country’s reform efforts in doubt.

Ruslan Ryaboshapka was removed in a parliamentary vote of no confidence on Thursday night, after Zelenskiy said he should be dismissed, despite objections by ambassadors from G7 countries, including the United States.

The U.S. and the European Union had supported Ryaboshapka, who was overseeing a major reform of Ukraine’s corrupt prosecutor’s office, which has been seen as a block on wider efforts to clean up the country following its 2014 revolution.

Ryaboshapka’s removal came a day after Zelenskiy replaced his reformist prime minister, Oleksiy Honcharuk, and much of his cabinet.

The two steps have caused major concern among Ukraine’s Western partners, international organizations and anti-corruption activists, who worry it signals a turn away from reform and instead points to the growing influence of oligarchs as well as pro-Russian forces seeking to turn Ukraine back toward Moscow.

“It is absolutely very bad,” Daria Kaleniuk, a campaigner who leads Ukraine’s Anti-Corruption Center in Kyiv, told ABC News on Friday. “It’s actually the first severe signs of a huge roll-back of the entire country in the reforms, and specifically in the rule of law reforms.”

The value of Ukraine’s bonds fell Wednesday amid fears the prime minister’s removal put in doubt a multi-billion dollar deal with the International Monetary Fund. The head of the National Anti-Corruption Bureau (NABU), which Ukraine’s Western partners helped set up, is now also thought likely to be fired.

Zelenskiy and his supporters have justified Ryaboshapka’s removal over what they said was slow progress in bringing prosecutions against former top officials and in high-profile investigations.

“My personal opinion is very simple: if there are no results – the person should not remain in their job,” Zelenskiy was quoted by Interfax Ukraine as saying before the vote.

Pressure from the oligarchs

But many observers have interpreted it as the result of pressure from a group of Ukraine’s powerful oligarchs. In particular, they said it pointed to the growing influence influence of Ihor Kolomoiskiy, a banking and media tycoon who helped fund Zelenskiy’s presidential campaign and owns the channel that aired his show.

Worries around Kolomoiskiy’s influence have centered on his efforts to regain ownership of Ukraine’s largest retail bank, Privat Bank, which was nationalized in 2016 over alleged mismanagement. The issue has become a crucial test for Ukraine, with the IMF warning that it will not agree to the assistance program if the bank is returned to Kolomoiskiy.

Until recently, observers said they believed Zelenskiy appeared to have maintained some distance from Kolomoisky. But in the last few months approval ratings for Zelenskiy, a former actor and comedian who won a landslide last April, have begun to drop.

Honcharuk had reportedly clashed with Kolomoisky over appointments at a state electric company, and his allies have told Ukrainian media he believes that confrontation sealed his fate.

Anti-corruption activist Kaleniuk and other observers said they also believed that pro-Russian groups, in particular oligarch Viktor Medvedchuk, a friend of President Vladimir Putin, had sought Ryaboshapka’s removal. In the vote to remove Ryaboshapka, Zelenskiy’s party needed the support of Medvedchuk’s pro-Russian party, Opposition Bloc.

The current favorite candidate to replace Ryaboshapka is a lawmaker from Zelenskiy’s party, Serhii Ionushas, a lawyer whose firm previously worked for Zelenskiy’s production company.

Ryaboshapka has blamed his ousting on “oligarchs and their minions”.

“I didn’t become anyone’s servant,” he told the parliament in a speech Thursday. “I was and still am independent. And you can’t force an independent prosecutor to do things, you can only fire him.”

The supporters of Ryaboshapka’s removal also criticized him for declining to support the investigation of Zelenskiy’s predecessor as president, Petro Poroshenko. Police have been building a treason case around Poroshenko over a ceasefire deal he struck with Russia in 2015.

The moves have horrified Western governments, which view it as an attempt at political revenge that jeopardizes Ukraine’s democracy.

Trump and Zelenskiy’s July phone call

Ryaboshapka was appointed by Zelenskiy weeks after the July phone call last year in which President Donald Trump pressured the Ukrainian president to open investigations into his Democratic rival, former vice president Joe Biden. In a partial transcript of the call released by the White House, Zelenskiy told Trump the incoming prosecutor will be “100% my person”.

Ryaboshapka, who previously worked for Transparency International, was well-regarded among anti-corruption activists and Western diplomats, who believed he was seeking real reform, a marked departure from his predecessors. He has also had to navigate the political squalls summoned by the impeachment saga. As part of the reforms, Ryaboshapka’s office had to audit all cases sitting on its books. Those included several involving the oligarch owner of the energy company Burisma where Biden’s son Hunter sat on the board and that has been at the center of Trump’s demands for an investigation. Ryaboshapka has said some of the Burisma cases are currently still being reviewed but has said the Bidens’ names are not mentioned in them and that there is no evidence of wrongdoing by them.

Kaleniuk said she feared that Ryaboshapka’s replacement might now be pressured into opening the investigations demanded by Trump, which she called “this fake story”.

Even as Americans’ attention has moved on from impeachment, in Ukraine some of the politicians and former officials involved in pushing the narrative of wrongdoing about Biden have continued to promote it. The effort has primarily been led by pro-Russian lawmakers, who have given a series of press conferences to present dubious documents while making outlandish accusations against Biden and the U.S. embassy in Kyiv under the Obama administration. And during the vote against Ryaboshapka, a pro-Russian lawmaker said he hoped the new prosecutor general would seek investigations against the Bidens and Burisma.

“I’m afraid that with help of these pro-Russian forces in Ukraine we will be forced again into the internal battles between Republican and Democrats in the United States,” Kaleniuk said.