Germany’s Economy Ministry has appealed a court ruling against a decision to allow the proposed takeover of a supermarket chain, a saga that has become politically awkward for the country’s vice chancellor.

Vice Chancellor Sigmar Gabriel, who is also the economy minister, in March overrode antitrust authorities’ decision to block the takeover by Edeka — Germany’s biggest groceries retailer — of some 450 supermarkets belonging to smaller rival Kaiser’s. Gabriel argues that his decision was necessary to protect jobs.

Last month, a Duesseldorf court suspended Gabriel’s decision. It found that the minister had conducted secret talks during the proceedings, creating the impression that he might not have been neutral.

Gabriel has strongly rejected the court’s arguments. He said Monday that his ministry has filed a full appeal to a federal court.