European regulators have cleared the $11 billion merger between American Airlines and US Airways.
The two airlines have agreed to give up one slot at both Heathrow and Philadelphia when their merger goes ahead as well as making “other commitments in order to induce entry on the London-Philadelphia route”.
The European Commission said it had been concerned that the merger of the two airlines would create a monopoly on the route between London and Philadelphia.
Joaquin Almunia, EC vice president for competition policy, said: "The commission could clear this transaction in the first phase given the commitments offered by the parties which address the competition concern we identified on the London-Philadelphia route.
“The commitments include a corresponding slot at Heathrow as well as far-reaching feeder arrangements to induce entry by a new competitor on the route.
“We are therefore satisfied that the competitive dynamics will be maintained so as to ensure choice and quality of air services for passengers on this route.”
The merger still has to be given clearance by the US Department of Justice which is reviewing the proposed deal over its impact on competition in the aviation market.
US Airways shareholders approved the merger last month.