British Airways, Air France-KLM and 11 other carriers are expected to be fined a total of about €800m (£690m) by EU antitrust regulators for fixing cargo prices.
The European Commission charged the carriers in December 2007 with participating in an air freight cartel, following raids on both sides of the Atlantic a year earlier that also involved the US Department of Justice.
"Thirteen airlines will be fined, of which six are non-European carriers," said a senior European source.
The Competition Commissioner Joaquin Almunia is set to announce the fine in Brussels this afternoon.
British Airways could be penalised by as much as €120m, the source said. Reports last month suggested it was facing a fine of between €60m and €80m.