The airline said: "Air France deplores the continuation of these strikes even though the period that opens does not allow to pursue any negotiation".
Societe Generale analysts warned the weaker earnings performance could lead to a rift between Air France and its profitable Dutch partner, KLM.
Unionised staff walked out for the 14th day on Monday as they press for a 5.1-percent salary increase this year as the company recovers from years of losses and restructuring.
Air France stock closed 9.8 percent lower at 7.30 euros, having earlier traded as low as 6.93.
He also said that the French government, which owns 14.3% of the Air France-KLM holding company, would not provide the carrier with a bailout, according to BFMTV.
France's finance minister has warned that the survival of strike-hit Air France was in the balance following the departure of the company's chief executive over a pay dispute.
Mr Le Maire told French news channel BFM TV: "I call on everyone to be responsible: crew, ground staff, and pilots who are asking for unjustified pay hikes". "The challenge is the survival of the company, which may disappear if it does not make the necessary competitiveness efforts", he added.More news: Narendra Modi in Chitradurga, Karnataka, accuses Congress of insulting Dr. BR Ambedkar
Air France-KLM boss Jean-Marc Janaillac announced his resignation Friday after staff at the carrier's French operations rejected a pay deal aimed at ending months of walkouts.
Air France-KLM reported a net loss of €269 million ($321 million) in the first quarter of the year.
Air France shares continued on their downward spiral today following the shock resignation of CEO Jean-Marc Janaillac over the weekend.
The company argued it must preserve its ability to stay competitive against low-priced airlines and big-spending Mideast and Asian carriers.
Air France has said that "nearly 85 percent" of its flights would be operating, including 99 percent of long-haul flights, 80 percent of its medium-haul flights to and from Charles de Gaulle and 87 percent of short-haul flights to Orly airport and elsewhere in France.
At the request of the board of directors, Janaillac will remain in his role as CEO and Chairman until the end of the company AGM on May 15 when "an interim governance solution" will be announced.
Others, including the more moderate CFDT union, which had urged Air France to back management's pay proposal, warned that "dialogue was blocked" and said the SNPL was too inflexible.