Icelandic authorities on Sunday removed restrictions on air traffic after lowering an aviation alert level at the Bardarbunga volcano in the south-east, a day after raising the alert to its highest level - red - amid fears of an eruption.
With the lower alert level, restrictions in the airspace have been lifted, Fridthor Eyddals, spokesman for national airport and air navigation operator ISAVIA, told dpa.
Early Sunday, several powerful earthquakes were registered at the Bardarbunga volcano, where activity increased a week ago.
Researchers however said that what was on Saturday believed to have been a subglacial eruption did not occur.
The Icelandic Meteorological Office said there were no signs that activity at the volcano, situated under the Vatnajokull glacier, is slowing down, and 'therefore an eruption cannot be excluded.'
The orange alert is the second-highest, meaning that the volcano 'shows heightened or escalating unrest with increased potential of an eruption.'
The red alert level designation - issued Saturday - means that an eruption is imminent or ongoing and that 'significant emission of ash' into the atmosphere is likely.