Thousands of protesters have demanded Czech Prime Minister Andrej Babis's resignation in downtown Prague, while his coalition partners discussed whether to quit the government.
The pressure against Babis followed a media report in which Babis's son said his father had wanted him to go into hiding to impede a criminal investigation into Babis and two of his children on suspicion they illegally took a 2 million-euro ($2.27 million) EU subsidy a decade ago.
In reaction, the opposition called a parliamentary vote of no confidence. The house speaker said on November 15 the vote would likely take place on November 23.
Billionaire businessman Babis, the EU and NATO member country's most popular politician, has repeatedly denied any wrongdoing and dismissed the report, published by news website Seznam.cz, as part of a media campaign against him.
In Prague's Wenceslas Square, several thousand people chanted "resignation" and "shame" on November 15. Some waved Czech and EU flags and carried slogans including "Down with Babis."
The center-left Social Democrats, a coalition partner of Babis's ANO party in the minority administration, have been considering "all options" regarding further action, party leader Jan Hamacek said.
If the government loses the no-confidence vote, it must resign. A new prime minister would be appointed by President Milos Zeman.
Babis could find support elsewhere to survive at the helm of the government. The far-right opposition SPD, an anti-EU and anti-NATO party, has indicated it may be willing to back a Babis-led cabinet without Social Democrat ministers if it changes some of its policies.
