( CNN ) -- Iceland will close two airports on Friday for the first time , a week after ash from an Icelandic volcano forced the shutdown of airspace over much of Europe and stranded thousands of passengers around the world , the Icelandic aviation authority announced Thursday . The Keflavik International Airport and Reykjavík International Airport will be closed beginning early Friday morning , the aviation authority said , according to a statement on the Keflavik airport 's website . Though the ash cloud originated in Iceland , the country 's airports have been spared from closure until now . Strong northwest winds had been blowing ash from the volcano , in the south of Iceland , out to sea and over Europe . `` Now the winds have died down , and the cloud is lingering around Iceland , '' said Chris Almond , a forecaster with Britain 's Met Office , the nation 's national weather service . Two other Icelandic international airports , in Akureyri and Egilsstadir , will stay open to all air traffic , the aviation authority said . The ash cloud is not expected to reach those cities , which are in the north and east of the island nation . Icelandair announced Thursday that trans-Atlantic passengers from the U.S. and Europe who would have stopped in Keflavik will be rerouted Friday via Glasgow , Scotland . Icelandair said that passengers traveling to and from Iceland will have the option of being re-routed through the Akureyri airport , a four-hour drive from Reykjavík . The airline is arranging bus travel between Akureyri airport and the Reykjavík Bus Terminal . Elsewhere in Europe , most airports appeared to be open on Thursday and are expected to be open Friday . But the cloud still caused flight disruptions Thursday . The British Ministry of Defence temporarily suspended non-essential flying Thursday after volcanic ash was found on some of its Typhoon fast jets . The closure of so much European airspace for nearly a week left untold numbers of travelers stranded , and it 's not clear how long it will take to get everyone home . Many airlines added or rearranged flights to try to clear the backlog . At its peak , the crisis affected 1.2 million passengers a day and 29 percent of all global aviation , according to the International Air Transport Association . It was the worst disruption of air traffic since the September 11 terrorist attacks in the United States in 2001 . Following those attacks , the United States closed its air space for three days , forcing Europe to postpone all transatlantic flights . The International Air Transport Association estimated earlier this week that the Icelandic volcano crisis cost airlines more than $ 1.7 billion in lost revenue through Tuesday . The crisis began after the volcano beneath the Eyjafjallajokull glacier erupted April 14 and sent a cloud of ash into the atmosphere . By the next day that cloud had reached Europe , where authorities quickly closed the airspace over safety fears . By Tuesday , however , airlines had started to complain that the measures were too restrictive . Ash levels in most parts of Europe , they said , were low enough to allow the safe operation of flights . Scientists in Iceland said Wednesday the volcano has decreased its ash output by 80 percent compared to the first day of eruption . Armann Hoskuldsson , a volcanologist at the University of Iceland , told a briefing that the volcano 's output is now `` insignificant , '' though it will continue to be active for a while . That reduction in volcanic activity appeared to be the main reason that flights resumed operating in Europe on Wednesday , along with European countries relaxing their restrictions on flight , according to a spokeswoman for Eurocontrol , an intergovernmental body that manages European air travel . In Britain , the Civil Aviation Authority ( CAA ) issued revised guidance on flying through volcano ash clouds , allowing airlines to conduct their own risk assessments and requiring them to report any ash damage to the authorities . The 27 countries of the European Union also agreed with Eurocontrol to split the airspace into zones based on their ash content and to allow flights in the unaffected areas , said Spanish Minister of Public Works Jose Blanco . `` Airspace was being closed based on theoretical models , not on facts , '' said Giovanni Bisignani , director general and CEO of International Air Transport Association . `` Test flights by our members showed that the models were wrong . ''
Keflavik International Airport , Reykjavík International Airport will be closed Friday . Change in winds means ash cloud is now lingering over Iceland , leading to closures . Comment: Most European airports were open Thursday and should be open on Friday .