The European Commission has warned Bulgaria’s state-run power firm that restrictions on where its electricity can be resold may breach EU antitrust rules.

It sent a ‘Statement of Objections’ to Bulgarian Energy Holding (BEH) saying the Commission has concerns the company “might be hindering competition” on the non-regulated wholesale electricity market in Bulgaria.

The statement said “a majority” of its power supply contracts suggested energy traders could resell the electricity either only within Bulgaria or only outside the country.

“The contracts also contain control and sanctioning mechanisms which allow BEH to monitor and punish customers who fail to comply with these territorial restrictions,” it added.

BEH told a news outlet: “The Bulgarian Energy Holding will analyse the statement of objection and will respond to the commission in the second half of 2014.”

The company is also being investigated by EU regulators over alleged restrictions to key gas infrastructures in the country.