In a potential setback for Google Inc., the European Commission’s competition chief said on Saturday that he may seek more concessions from the search giant to resolve an antitrust investigation into its monopoly power. The statement comes as Microsoft Corporation is drumming up opposition to a proposed settlement between the Commission and Google that was unveiled in February.

European competition commissioner Joaquin Almunia said in an interview with Bloomberg TV that he has received “new data” and “new arguments” from objectors to the proposed settlement. The European Union “will try to extract from Google solutions to these arguments,” Almunia said.