Conservative premier Mateusz Morawiecki told reporters on Friday that he had read a report by the Central Anti-Corruption Bureau on Marian Banaś, the head of Poland’s powerful Supreme Audit Office (NIK).
The office is Poland’s top state audit body and is tasked with monitoring public spending.
Morawiecki said: "I came to the conclusion that the findings of this report should prompt Mr. Marian Banaś to resign."
He added: "I think that the head of the Supreme Audit Office will resign today. If this does not happen, we have, so to speak, a plan B.” Morawiecki did not give further details.
Banaś is a former finance minister. In the 1980s he was imprisoned by the communist regime for being part of the Solidarity pro-democracy movement.
In September this year, private broadcaster TVN suggested that Banaś had links to pimps and that, in a declaration of assets, he had understated his income from renting out a residential building in Kraków, southern Poland.
Banaś said he did not manage the hotel shown in the exposé by TVN, which is critical of the conservative government.
He filed a lawsuit, demanding an apology and claiming that the TVN report was an attempt to blacken his name.
Poland’s ruling conservative Law and Justice has vaunted its image as an honest party, in contrast to what it says was the previous corruption-ridden government headed by its arch-rival, the Civic Platform, which was in power until late 2015.
Law and Justice (PiS), allied with two smaller groupings in a United Right coalition, secured a second term in power in a parliamentary election on October 13.