MADRID, Oct 7 (Reuters) - A buildup of ash and dust from the erupting Cumbre Vieja volcano on the runway forced authorities in Spain"s La Palma to close the island"s airport on Thursday, air traffic operator AENA (AENA.MC) said. Other airports in the Canary Islands" archipelago off North Africa remained open, however, and an AENA spokesperson said the ash cloud was unlikely to pose any wider risks to air travel for now. It is the second time that La Palma"s airport has been shut due to ash buildup since the eruption began on Sept. 19."The La Palma Airport is inoperative due to ash accumulation. The established protocols are being applied. Safety is the priority," the operator said in a post on Twitter.In 2011, sweeping closures of European airspace due to an ash cloud from the Eyjafjallajokull volcano in Iceland disrupted travel plans for millions of passengers in Europe and elsewhere, and cost airlines over a billion euros in revenues. The volcano on La Palma has been blasting out jets of red-hot lava for more than two weeks, laying waste to hundreds of buildings and farms, and forcing the evacuation of thousands. The airport was closed on Sept. 25 but reopened the following day after workers swept volcanic ash off the runway.