BRUSSELS, Belgium: The European Union approved "in principle" Boeing's $15 billion megamerger with McDonnell Douglas after the aircraft manufacturer made key concessions on exclusive supply contracts and the sharing of aviation technologies. The preliminary agreement temporarily averts a trade war between the United States and the EU which threatened to erupt if the consortium vetoed the Boeing-McDonnell arrangement. To secure EU approval, Boeing offered to terminate agreements which made Boeing the sole supplier of jets to several U.S. airline, and promised to grant competitors access to certain aviation technologies. Those concessions should assuage European fears for Boeing's last major competitor, European plane-maker Airbus Industrie, which has been steadily losing market share to the American company. Calling his approval preliminary, EU antitrust chief Karel Van Miert said more time was needed to read the fine print of Boeing's offers before a formal go-ahead is issued. A green light is expected as early as next week. While the Europeans could not have blocked the merger, they could have prevented Boeing from setting up shop anywhere in the soon-to-be-enlarged Union, or fined the aviation giant as much as $4.8 billion if it went ahead with the merger without community approval.