French oil major Total SA said Wednesday that a strike has begun affecting output at its 155,000-barrels-a-day refinery in Provence, southern France, after a trade union called for a nationwide walkout. The strike is disrupting Total's production of refined products at a time when the French company, Europe's largest refiner, has committed to ship more gasoline to the United States to help offset outages caused by Hurricane Katrina, The Associated Press reported.