Air France said Wednesday that last month's two-week strike would have an impact of around 500 million euros ($631 million) on its bottom line for this year.

Financial Director Pierre-Francois Riolacci said the estimate took into consideration lost revenue during the strike as well as knock-on effects stemming from disgruntled passengers staying away in the future.

He acknowledged, though, that those knock-on consequences were harder to gauge, but insisted there would be a grave impact on the final quarter of the year and the first months of 2015 as Air France battled to win back its reputation.

Transavia in focus

"We made some savings like in aviation fuel, because the planes were not flying," Riolacci said. "On the other hand, we had additional costs by putting passengers up, compensation or buying tickets from our competitors, which we did not always get at the best price."

Pilots at Air France waged the longest strike in the company's history between September 15 and 28 in protest of the carrier's initial plans to expand its low-cost subsidiary Transavia France abroad.

The pilots were worried their flights could be replaced by Transavia services or that the company would seek to use the cheaper Transavia staff.

hg/sgb (AFP, AP)