KLM plans to lift its stake in Scandinavian airline SAS AB to a controlling holding, as it looks to extend consolidation in European aviation and better compete with rivals Deutsche Lufthansa AG and IAG SA.

Ryanair was among airlines that announced widespread disruptions, saying in a statement it canceled more than 400 flights affecting 70,000 passengers. The company said the strike affects all its flights over French airspace, as well as traffic in and out of French airports, and urged the European Union to reform air traffic rules.