French aviation unions warned on Sunday they expected major air traffic disruptions this week as workers including pilots, flight attendants and ground staff launch a nationwide four-day strike.

"The movement will be very well followed. Saying how many is always complicated, but there will be a lot of people on strike," the head of the powerful SNPL pilots' union, Yves Deshayes, told AFP.

The unions voted Friday for strike action on February 6-9 to protest a draft law that will require aviation workers to give 48 hours notice before taking strike action.

The bill was approved by France's lower house last month and is being studied in the Senate.

Leading French carrier Air France has insisted the effects of the strike will be limited, saying it will be able to run more than 80 percent of its short- and medium-haul flights and more than 85 percent of its long-haul flights.

But union officials were sceptical.

"They are making a bet and I think Air France's bet is very optimistic," said Franck Mikula, the head of the UNAC flight attendants union.

Aeroports de Paris, which runs the capital's international airports including global hub Charles de Gaulle, said it would mobilise teams of employees on Monday to help passengers deal with the strike.

It recommended passengers check with their airlines before departing to catch flights.