Liberty Global is offering concessions in an effort to secure European Union antitrust approval for its $1.5 billion bid for KPN’s Belgian mobile unit, according to the European Commission. Liberty Global submitted its offer on Monday. Details of the offer were not released. The Commission’s new date to decide on whether to clear the deal or open an investigation Oct. 5th instead of Sept. 21st. Margrethe Vestager, European Competition Commissioner, signaled tougher regulations towards telecoms mergers by interfering a plan by TeliaSonera and Telenore to join forces in Denmark after they failed to deliver enough concessions.