Air traffic in much of northern Europe was halted Thursday by ash from a volcanic eruption in Iceland, aviation authorities said.

“Due to ash, air traffic on the sea area between Scotland, Norway, northern Sweden, Britain, Norway and northern Finland is being limited,” Finland’s airport agency Finavia said.

A volcanic eruption in Iceland spewed black smoke and white steam into the air Wednesday..

Britain’s National Air Traffic Service said that following advice from the Met Office weather service it had restricted the number of aircraft flying into British airspace.