European transport ministers agreed to ease, from Tuesday, restrictions on flights imposed due to the ash cloud emanating from an Icelandic volcano, the EU commission announced.

"From tomorrow morning on, we should progressively see more planes start to fly," EU Transport Commissioner Siim Kallas told reporters after lengthy videoconference talks between European transport ministers.

"There cannot be any compromise on safety. All the decisions must be based on scientific evidence and expert analysis," he added, as European airlines and passengers endured a fifth day of flight cancellations.

The Irish Aviation Authority said in a statement that there would be "an interim, European-wide response to the airspace restrictions arising from the volcanic ash cloud.

"The response will ease restrictions, and this will facilitate the commencement of limited operations," from Tuesday morning.

"In low contaminated areas, states should allow airlines to operate, fully supported by shared data, including advice from the scientific community," the Irish statement said.

A "limited no-fly zone," including buffer areas around areas where the volcanic ash makes flights hazardous, will be maintained, the Irish Aviation Authority said.

In areas where there was no contamination there would be no restrictions, it added.

"Normal operations are not expected to be in place for up to three or four days."

Separately Britain, France and others announced that they would begin lifting their flight bans from Tuesday.