British Airways, Air France KLM and nine other airlines have been fined a total of €800 million by the European Commission for being involved in an illegal cartel.
The airlines were found guilty of conspiring on the prices they charged for the transport of cargo between December 1999 and February 2006.
The EC’s vice president for competition Joaquín Almunia said: "It is deplorable that so many major airlines coordinated their pricing to the detriment of European businesses and European consumers.
“With today's decision the Commission is sending a clear message that it will not tolerate cartel behavior.”
Air France KLM received the heftiest fine, at €340 million.
British Airways was fined €104 million, Singapore Airlines €74.8 million and Cathay Pacific €57 million.
Scandinavian carrier SAS was given an increased penalty (€70 million), as it was previously fined in a cartel case in 1998.
The other airlines fined were: Air Canada, Cargolux, Japan Airlines, LAN Chile, Martinair, SAS, and Qantas.
The EC said that when deciding the amount each airline should pay, it took into account “the sales of the companies involved, the very serious nature of the infringement, the EEA-wide scope of the cartel and its duration”.
Lufthansa also took part in the cartel, but received immunity after it acted as whistleblower to the EC on the covert deals.