Air France and Ryanair clashed over subsidies after the French carrier accused its budget rival of putting pressure on regional authorities to give unfair support as the price of using their airports.
Air France said it had complained to the European Commission about what it described as "open-ended subsidies" in the form of discounts, preferential treatment and marketing help from regional airports in violation of European rules.
Ryanair hit back, saying it had not received any such state aid whereas Air France had.
"We pay no attention to false claims from high-fares, fuel- surcharging airlines like Air France. They can't compete with Ryanair so they complain instead. Ryanair is investing millions in regional French airport whereas Air France ignores them," Ryanair spokesman Stephen McNamara said in an email response.
Air France said it had filed a complaint to the European Commission at the end of last November. The move came to light in a newspaper report earlier today.
The airline, part of the Air France-KLM group, said in a statement that not only had Ryanair received unfair help in exchange for using regional airports, but had done so on the back of traditional carriers such as Air France.
"The aid obtained by Ryanair is often financed by the proceeds of landing fees paid by other airlines operating at those airports," the privatised French airline said.
Reuters