Australia's Qantas Airways said fight disruption on its European routes due to the Icelandic volcanic ash cloud was costing it about AU$1.5 million (US$1.37 million) a day.

On April 19, Qantas canceled flights to and from Europe for the next two days. The airline canceled seven flights from Europe and five outbound flights for April 20 and April 21.

"Next available services to Europe are not known at this time and cannot be confirmed until official notification from European authorities on when flights can resume," the airline said in a statement.

Qantas warned of days of flight delays due to backlog once flights resume.

"Qantas will be doing everything to meet passenger needs once flights into Europe are able to resume however access to UK and European airports will be difficult due to the backlog of flights from around the world," it said.

"This situation would be likely to continue for some days."