Ukrainian President Volodymyr Zelensky called on parliament to dissolve the constitutional court, as hundreds of people gathered on Friday to protest a ruling to block a number of anti-corruption laws.
Zelensky late Thursday submitted the bill called "renewing public confidence in constitutional justice", which would void the court's ruling to block much of the anti-corruption legislation and begin the process of selecting new judges.
The constitutional court's move, prompted by a request from around 50 pro-Russian lawmakers, has sparked an outcry in Ukraine, with hundreds of people demonstrating outside the court in the capital Kiev on Friday.
The protesters, including students and anti-corruption activists, held placards reading "Corrupted court of Ukraine" and "Out the pigs of the constitutional court".
Iryna Shyba, a 28-year-old anti-corruption activist told AFP that without proper legal oversight, "most officials will steal with impunity, plunder the Ukrainian budget and Ukraine".
Riot police on the scene did not intervene even after protesters threw smoke grenades into the court building.
The head of the presidential administration Andriy Yermak claimed Friday in a meeting with G7 ambassadors that the court had been moved to drop the corruption measures as a result of "external influence," without further explaining.
"The president will not stop on the path of reform and fight against corruption," he added.
Constitutional court chairman Oleksandr Tupytsky responded to Zelensky's bill by saying it bore signs of a "constitutional coup".
"The aim of all of this is to create a neutral, obedient court," he said during a news conference.
- 'Make or break' the presidency -
"I am not accusing the president, but his entourage is doing a bad job," Tupytsky added.
The constitutional court on Wednesday ruled that a number of anti-corruption laws were unconstitutional, including one on free public access to officials' asset declarations.
Zelensky, a 42-year-old former comedian, came to power last year pledging sweeping political change and to root out corruption.
On Thursday, he convened an emergency meeting of the National Security Council, saying the court's ruling was a "devastating" blow to the ex-Soviet country's anti-corruption reform drive. Lawmakers should undo the damage, he added.
Zelensky -- weakened by losses in local elections last week -- may struggle to win support for his bill in parliament, said Timothy Ash, a senior emerging markets strategist at Bluebay Asset Management.
"A major crisis is unfolding which could either make or break the Zelensky presidency," he said.
Ukraine's ally the United States is distracted by its own upcoming presidential election and the crisis suits Moscow "just fine," Ash said.
Russian President Vladimir Putin "will seek to exploit that to the full," he added.
After a 2014 popular uprising, the West demanded tangible progress in Ukraine's fight against corruption, and Kiev established various anti-corruption bodies such as the National Agency for Preventing Corruption and the specialised court.
The EU has warned that its visa-free regime for Ukraine could be suspended if Kiev does not do enough to combat corruption, considered by the bloc to be the country's top risk.
According to Transparency International, Ukraine ranked 126th out of 198 countries on the watchdog's corruption perception index in 2019.