ACzech court has blocked electricity producer CEZ from signing an $18bn contract with South Korea’s KHNP to construct a new nuclear power plant, following a complaint filed by French energy company EDF.

In late April 2025, EDF filed a complaint against the Czech competition regulator, the Office for the Protection of Competition (UOHS), after the regulatory authority rejected EDF’s appeal regarding a tender to select a supplier for two nuclear reactors.

Reuters reports that the Czech government, the largest stakeholder in CEZ, planned to sign the contract with KHNP on Wednesday 7 May.

The contract is the largest public procurement deal in Czech history and a crucial component of the country’s energy strategy to replace coal and ageing nuclear units.

The Brno Regional Court stated: “If the contract were concluded, the French bidder would inadvertently lose the possibility of winning the public contract, even if the court rules in its favour in litigation.”

The decision can be appealed at the Supreme Administrative Court and CEZ is reportedly planning to do so.

In 2025, CEZ selected KHNP to construct two 1GW units to expand its Dukovany nuclear plant – KHNP’s first project in Europe.

Since then, EDF has sought to overturn the decision through various channels.

In late April 2025, the government agreed to acquire an 80% stake in CEZ subsidiary EDU II, established for the construction of the new units, to alleviate CEZ’s financial burden. This subsequently boosted CEZ shares.

UOHS affirmed its stance on its decisions that dismissed EDF’s complaint.

A UOHS spokesperson remarked: “This is a procedural decision. It does not indicate how the court will rule in the merit of the case. We believe our decisions were correct.”

The government conducted the tender under a national security exemption, which suspends certain standard procurement requirements.

CEZ and the government have asserted that KHNP’s offer surpassed EDF’s offer.

EDF has welcomed the court’s decision, stating that it provides necessary time for a thorough assessment of any potential infringement of its rights. It also noted that it is pursuing the case at the European Commission.

CEZ has indicated that it would seek damages if the courts rule in favour of its selection.

KHNP reserves the right to pursue its legal actions, stating: “The attempt to challenge the result through legal manoeuvres is regrettable and represents a direct attack on the principles of fair competition.”