Air France-KLM announced Wednesday a first quarter net loss of €197 million ($283 million) and said the outlook was uncertain for the rest of the year.
In the same period last year, the company had reported a €736 million net profit.
Air France said first quarter sales this year rose 8.7 percent to €6.22 billion, with passenger numbers up 9.4 percent on a 10.1 percent increase in capacity.
Cargo activity rose a slight 1.9 percent on a capacity increase of 6.2 percent, the airline said.
The airline said it would reduce a planned increase in capacity for the coming months, given the destabilising effects of the Japanese earthquake, the ongoing eurozone debt crisis and turmoil in Africa and the Middle East.