EU transport ministers are urging Europe to ease travel restrictions after flights were cancelled for the fourth day, the BBC said.
"We cannot just wait until this ash cloud dissipates," EU Transport Commissioner Siim Kallas said in the BBC.
Airlines said that Europe was overacting to the debris in the air caused by the volcano in Iceland, the New York Times reported.
Airlines said that Europe should not be relying on incomplete computer data models but instead on the real-world safety tests in the air above Europe, the Times said.
European transit monitors agreed to meet in Brussels Monday to re-evaluate how and when planes will be allowed to fly again, the BBC said.