Air France has said several of its pilot unions have called a strike for 6-9 September.

The airline said its flight schedule would be severely disrupted on the four days, with medium- and long-haul flights most affected.

It promised customers it would "do its utmost to minimise the inconvenience" and "deplored" the action by pilots.

Announcement of the strike came after the failure on Wednesday of negotiations over contracts.

The airline said information on the flight schedule for 6-9 September would be available on its website from 1100 GMT on Thursday.

Less dependent

Also on Wednesday, Air France reported a 18.5% fall in net profit to 159m euros for the first quarter of its financial year.

The result was a better one than many analysts had expected, amid the downturn in the global aviation industry.

Analysts said Air France had not suffered as badly as some of its peers because it was less dependent on the hard-hit transatlantic market than many other big European carriers.

It had also picked up valuable customers after the collapse of Swissair and Belgium's Sabena, they said.

Air France said its financial performance was "very positive... despite a particularly difficult context".

State sell-off

Earlier this year, the French Government said it planned to give up its majority stake in Air France, while remaining a major shareholder.

The government is currently the airline's biggest shareholder, owning 54.4%.

According to reports, the government intends to cut its stake to less than 20%.