Iceland Met authorities have again raised the warning code for aviation to red after an eruption near the Bardarbunga volcano.
The red alert is the highest warning and means "eruption is imminent" with "significant emission of volcanic ash likely".
Icelandic Air Traffic Control has closed the airspace above the eruption site.
“The Icelandic Met Office has raised the aviation colour code over the eruption site to red and the Icelandic Air Traffic Control has closed down the airspace from the earth up to 18,000 feet,” Iceland’s National Crisis Coordination Centre said.
“No volcanic ash has been detected with the radar system at the moment ... Seismic eruption tremor is low indicating effusive eruption without significant explosive activity.”
In 2010 much of Europe’s airspace was shut for six days, affecting more than 10 million people, after Iceland’s Eyjafjallajokull volcano erupted.
After the ash report published