Britain and Ireland were closing parts of their airspace again today after a fresh cloud of ash arrived from the Icelandic volcano that caused air travel chaos in Europe last month. Ryanair cancelled a flight to Malta from Edinburgh, due to arrive at 11.10 a.m.
British regulators ordered an airspace shutdown over parts of Scotland and Northern Ireland from 8:00 am for 12 hours for most affected airports, warning that high ash levels could damage plane engines.
"Forecasts show that levels of ash in the atmosphere over Scotland and Northern Ireland will exceed the concentrations that engine manufacturers have agreed are safe for operations," said Britain's Civil Aviation Authority (CAA).
"Unfortunately, this means that the CAA anticipates all Scottish and Northern Ireland airports will be closed from 8 a.m. local time (Wednesday)."
According to meteorologists, the cloud over Britain had "increased in density as ash emissions from the Icelandic volcano... have become stronger," said the air watchdog in a statement.
Irish aviation chiefs meanwhile said restrictions would be introduced at some airports from 9 am.
The new shutdowns followed a closure of Irish, Northern Irish and some Scottish airspace for several hours yesterday, which caused the cancellation of hundreds of flights and travel misery for thousands of passengers.
Airspace across Europe was closed for up to a week last month after the eruption of Iceland's Eyjafjoell volcano, but was re-opened after emergency talks between European governments, airlines and regulators.
The CAA said some Scottish airports, including Glasgow, would likely be closed for 12 hours until 7:00 pm (1800 GMT).
In Northern Ireland, Derry airport would shut down early Wednesday for 12 hours, and airports in Belfast would only close later in the day, said the air safety watchdog.
Other airports were also at risk of closure, including Edinburgh and some in the northwest of England, said the regulator.
But regulators did not indicate that the ash was an imminent threat to airports further south, including London Heathrow, Europe's busiest air hub.