Bulgaria‘s state-owned energy company may be breaking European Union (EU) laws by imposing territorial restrictions on the resale of its electricity, the EU‘s executive warned, according to DPA.

Energy prices have been a sensitive issue in Bulgaria, where mass protests over high bills and low salaries led to a government resignation last year.

The European Commission (EC) warned Bulgarian Energy Holding (BEH) that it “might be hindering competition … by imposing restrictions on where the electricity supplied by BEH may be resold,” it said in a statement.

According to the commission, BEH stipulates in most contracts either that its electricity may only be resold within Bulgaria, or that it can only be exported. The contracts also include mechanisms to “monitor and punish” customers who fail to comply.

“The commission‘s provisional finding is that these territorial restrictions constitute an abuse of BEH‘s dominant market position,” it wrote, adding that such behaviour reduces market efficiency and raises artificial trade barriers.

The EU‘s executive launched a separate investigation into BEH last year, over suspicions that the company and its subsidiaries were illegally hindering competitors from accessing key gas infrastructures in Bulgaria.