The legislation has also drawn rebukes from European Union officials and international rights groups.
President Volodymyr Zelenskiy, under pressure as the change threatened to endanger his public support at a critical time in the war, convened the heads of Ukraine's key anti-corruption and security agencies in a response to the outcry against his decision to approve the new law that was passed by parliament.
"We all hear what society says," Zelenskiy wrote on Telegram after the meeting. But he insisted the new legal framework was needed to crack down harder on corruption.
"Criminal cases should not drag on for years without verdicts, and those working against Ukraine must not feel comfortable or immune from punishment," the Ukrainian leader said.
He said all government agencies agreed to work constructively and respond to public expectations for fairness and effectiveness.
A detailed joint action plan is expected within two weeks, aimed at addressing institutional weaknesses, removing legal hurdles, and ensuring justice across the board, he said.
Thousands of people gathered in Kyiv and other cities across Ukraine on Tuesday evening to urge Zelenskyy to veto the controversial bill. After Zelenskyy approved it, activists called on social media for another demonstration in Kyiv on Wednesday evening.
The legislation tightens government oversight of two key anti-corruption agencies. Critics say the step could significantly weaken the independence of those agencies and grant Zelenskyy's circle greater influence over investigations.
Fighting entrenched corruption is crucial for Ukraine's aspirations to join the EU and maintain access to billions of dollars in Western aid in its fight against Russia's three-year invasion.
"Limiting the independence of Ukraine's anti-corruption agency hampers Ukraine's way towards the EU," German Foreign Minister Johann Wadephul warned in a post on X
EU Defence Commissioner Andrius Kubilius, also on X, noted: "In war trust between the fighting nation and its leadership is more important than modern weapons - difficult to build and to keep, but easy to lose with one significant mistake by the leadership."
The Ukrainian branch of Transparency International criticised parliament's decision, saying it undermines one of the most significant reforms since what Ukraine calls its Revolution of Dignity in 2014, and damages trust with international partners.
It accused authorities of "dismantling" Ukraine's anti-corruption architecture.
Zelenskiy said the new law clears out "Russian influence" from the fight against corruption and ensures punishment for those found guilty of it, after what he said were years-long delays in criminal proceedings involving huge amounts of money.
"The cases that have been lying dormant must be investigated," Zelenskiy said in a Telegram post.
"For years, officials who have fled Ukraine have been casually living abroad for some reason - in very nice countries and without legal consequences - and this is not normal."
He didn't provide examples of what he said was Russian interference.
