Air traffic disruption triggered by the eruption of Iceland's Grimsvoetn volcano was reduced to parts of Norway and Sweden Thursday, as the last spits of hot vapour seeped out of the crater.

"Today is good except for the mid-part of Norway/Sweden -- and that will be dissipating," Brussels-based Eurocontrol said in regular Twitter updates.

"Only light ash in Poland today and that is clearing away overnight. Looking good."

Thousands of passengers had their travel plans ripped up after Saturday's eruption, with hundreds of flights over Scotland and Germany among the worst affected this week, although far short of the scale of disruption caused by another eruption on Iceland just over one year ago.

"The volcano is still active but there is only steam smoke, no ashes coming out," said Hjalmar Bjorjyinsson, superintendent at the national police, speaking for the Icelandic crisis management team.

"It's not quite finished but I hope it will be tomorrow or during the week-end," she added.