Several Air France unions on Thursday announced they would observe strikes on May 3, 4, 7 and 8 as part of the ongoing wage increase dispute with the carrier's administration.
"We must continue to keep up the pressure for our wage demands," the unions said in a statement, arguing that their aim is to "sign an agreement that is reasonable for everyone."
The Air France management slammed the call for new strikes as "incomprehensible" amid ongoing negotiations.
The unions have previously led 11 days of strikes. Pilots and cabin crew to ground staff are observing strikes in a bid to pressure the management to increase staff salaries by 6 percent across the board.
The Air France management initially deemed the increase as "impossible" and has put on the table a draft agreement providing a general increase of only 1 percent to be paid in two stages.
However, the carrier management later on said it proposed unions to cover multi-year pay raises negotiations between 2019 and 2021 and a doubling of the salary revaluation planned for 2018.
The Chief Executive of the French flag carrier Jean-Marc Janaillac said Thursday he will put the company's latest offer to a vote of all the 46,771 employees of Air France (under French contract) and threatened to resign if the proposals are rejected.
Prime Minister Edouard Philippe praised his stance as "courageous" and warned that a negative vote could further harm the company.
"If the consultation did not produce the results he hoped for and he took the consequences, everyone should fasten their seat belts because the turbulence will not be minor," he told French radio Europe.
"A company that loses its boss in these conditions is not well placed to face the future."
The industrial action, affecting about 30 percent of Air France flights comes as France is facing a wave of strikes in several sectors, with state railway operator SNCF planning a total of 36 days of rolling strikes -- which started on April 3 -- over the next three months, to protest government reform plans.
Students, trash collectors, electricity and energy sector staff are also among those taking part in what has been called the biggest wave of industrial unrest since President Emmanuel Macron's election last May.
Seven main public sector trade unions called for a one-day strike on May 22 to protest Macron's plans to reform the eurozone's second-largest economy.
