Oct. 31 (Bloomberg) -- Air France's 15,000 cabin crew disrupted flights for a third day in protest at cuts to staffing levels, grounding about 12 percent of services including long- haul trips to Atlanta, Los Angeles, Montreal and Washington.

Air France-KLM Group fell 6.9 percent in Paris after its French unit said 88 percent of 1,000 scheduled flights would operate today, with about 120 halted yesterday and 130 on Oct. 29. Unions put the cancellations at 171 and 209 respectively.

Cabin-crew unions have called a strike for Oct. 29 to Nov. 2, spanning the All Saints Day holiday, one of France's busiest travel periods, as they seek to halt plans to cut staff levels on Airbus SAS single-aisle jets. Air France is seeking to cut costs after an earnings slump forced the departure this month of Pierre-Henri Gourgeon, its chief executive officer.

"You don't want strikes but if it means they're confronting issues that need confronting then it could be good for the long term," said Jonathan Wober, an analyst at Societe Generale in London who cut his rating on Air France-KLM to "sell" from "hold" today because of the carrier's traffic-growth outlook.

Air France-KLM fell 41 cents to 5.51 euros in the French capital, where the company is based. Europe's No. 1 airline has lost 60 percent this year, the worst performance on the six- member Bloomberg EMEA Airlines Index, which is down 32 percent.

"Clients are being held hostage by a five-day strike for which there's no reason," Air France said yesterday. "Management negotiated day and night for 10 days and responded favorably to 90 percent of the flight attendant unions' demands."

The Paris airports of Charles de Gaulle, Europe's second busiest, and Orly, as well as the terminal in Marseille, are among those affected. The dispute is deepening as Australia's Qantas Airways Ltd. resumed flights today after a labor regulator barred stoppages that prompted the carrier to ground its fleet, stranding about 80,000 passengers over the weekend.

Air France is trying to restrict cancellations to high- frequency European routes, where it's easier to rebook seats, spokeswoman Brigitte Barrand said today by phone. U.S. services were halted because the company was able to shift people to services flown by SkyTeam alliance partner Delta Air Lines Ltd.

Read more: Air France Halts 12% of Flights as Crew Strike for Third Day