Says the Telegraph:
"It is the first time since the warning system was adopted two years ago that such a severe warning has been issued, and is just one level below the “red alert” for an imminent eruption.
British holidaymakers have been warned there is a risk of “significant disruption” to air travel if an Icelandic volcano erupts later this week.
Iceland has issued its most severe volcanic eruption warning for two years because of earthquakes at the Bardarbunga volcano, which lies under a glacier in the centre of the country.
Four years ago the eruption of the Eyjafjallajokull volcano in Iceland caused an ash cloud that grounded 107,000 flights over an eight-day period and affected 10 million passengers.
The UK Civil Aviation Authority insisted today that huge advances in forecasting ash clouds, testing their density and determining safe ash levels for flying mean far fewer flights would have to be cancelled if Bardarbunga blows.
But an independent air safety consultant warned that there would still be major problems for air travellers if the circumstances of the 2010 eruption were repeated."