Ash cloud grounds flights in Scotland and Ireland

DUBLIN/LONDON (Reuters) - A cloud of abrasive volcanic ash drifting south from Iceland disrupted flights to and from Ireland and Scotland anew on Wednesday.

Britain's Civil Aviation Authority reopened Edinburgh airport at 1800 GMT on Wednesday and said it would lift restrictions on all other main Scottish airports from 0000 GMT on Thursday.

Airspace in Ireland was to start reopening from 0300 GMT on Thursday, Irish aviation officials said, but Northern Irish airports were to remain closed until at least 0600 GMT.

The latest disruption signaled that travel hold-ups would continue into the summer holiday period because of ash being blown from the same volcano in Iceland that caused mayhem for 10 million travellers last month.

The European air traffic agency Eurocontrol said about 300 of 29,000 scheduled flights were likely to be canceled across Europe on Wednesday. "The situation is not expected to improve in this area during the day," the agency said in a statement.

"The whole of Ireland, west Scotland and northwest England could be affected, with risk to operations at Manchester and Liverpool airports," it continued.

In addition, according to Eurocontrol, roughly 900 flights in Greek airspace would be canceled assuming a general strike in Greece against austerity plans lasted until midnight.

ASH CLOUD STAYING?

Britain's official weather forecaster, the Met Office, said the cloud would continue to drift west overnight into Thursday, suggesting the majority of airports would be outside the no-fly zone by 0600 GMT.

British Airways said it had restarted flights to Edinburgh on Wednesday evening and planned to operate a full schedule to Scotland on Thursday.

Irish budget airline Ryanair also canceled flights to and from Glasgow Prestwick and the Northern Irish cities of Belfast and Derry until 2300 GMT.

It also warned that services at the English airports of Liverpool, Bristol, Leeds and Manchester could be affected.

Britain's Civil Aviation Authority said, based on current forecasts, it did not expect problems in the southeast, where the major airports serving London are located.

"The situation remains changeable, so passengers expecting to travel today and tomorrow from airports in Scotland, Northern Ireland, the northwest of England, Wales and the West Country should contact their airlines to check whether their flight is operating," the CAA said in a statement.

Much of European air traffic was grounded last month because of the spread of ash from the erupting volcano under the Eyjafjallajokull glacier in Iceland. Some 100,000 flights were canceled and millions of passengers stranded.

Tuesday was the first test of a European system of progressive closures, including partial no-fly zones, introduced after the ash cloud prompted a blanket ban that was criticized by airlines forced to ground thousands of flights in April.

European transport ministers have agreed to set safety limits for flying through the ash, which can paralyze jet engines, and to unify European airspace.

Last month's airspace closures cost Europe's airlines 1.5 billion to 2.5 billion euros ($2 billion-$3.3 billion), the European Commission has estimated.

(Additional reporting by Keith Weir and Caroline Copley in London, Philip Blenkinsop in Brussels, and Andras Gergely in Dublin; Editing by Jon Boyle)