Poland’s state-owned railway company PKP has asked a Warsaw court to annul the sale last year of its utility business PKP Energetyka to private equity fund CVC Capital Partners, PKP said on Friday.

CVC bought PKP Energetyka from the state railway company in July last year for 1.41 billion zlotys ($367 million) excluding debt, or 1.97 billion zlotys including debt.

The sale was criticised by the then opposition Law and Justice (PiS) party, which won elections in October. PiS has said PKP Energetyka is key to Poland’s energy security and should not be controlled by a private fund.

“We confirm filing a motion (to the court),” a PKP spokeswoman said, confirming a report by state-owned news agency PAP.

CVC said it did not know the content of the motion, nor any circumstances during the privatisation process that would justify filing such a motion.

“The privatisation process was fully transparent, in line with the law and has been verified by the prosecutors office and the Supreme Audit Chamber revealing no irregularities,” said the representative of CVC for Poland, Krzysztof Krawczyk.

PKP Energetyka’s spokesman said the situation was not affecting the functioning of the company.

Since coming to power, PiS has called a halt to privatisations, changed management in almost all state-run companies and questioned the rationale and pricing of the previous government’s stake sales.

For example, it has questioned its predecessor’s privatisation of chemicals group Ciech and the sale of some of the state’s shares in miner KGHM.

In April, anti-corruption agency CBA raided the Warsaw offices of and its majority owner Kulczyk Holding in an investigation into the privatisation.

Market sources have told Reuters that CVC is eyeing a number of assets for sale in Poland, including Nasper’s Allegro, convenience store chain Zabka owned by private equity firm Mid Europa, as well as central and eastern European beer brands put on sale by SABMiller.