Reykjavik: Airlines began cancelling flights to Britain late on Monday because of an ash cloud from an Icelandic volcano reaching its airspace, although experts expected no repeat of travel chaos from an eruption a year ago.
Britain`s Met Office forecast the plume of ash from the Grimsvotn volcano would cover the Irish Republic, Northern Ireland, Scotland and parts of northern England by 0600 GMT on Tuesday.
Worries about the effect of the ash cloud pushed forward President Barack Obama`s planned departure from Ireland and he arrived on Monday night in Britain to begin a state visit.
The Irish Aviation Authority said flights to and from Ireland could be disrupted later in the week but did not expect problems in the next 48 hours. Iceland`s main airport reopened late on Monday, while other parts of Europe were on alert.
With the ash cloud approaching, airlines began cancelling flights over the UK, raising the specter of big losses for airlines already facing sky-high fuel costs.
British Airways grounded all flights from London to Scotland until 2 p.m. (1300 GMT) on Tuesday as a precautionary measure, a spokeswoman said.
Flybe, EasyJet and Aer Lingus all said they were cancelling some of their flights to and from Scotland on Tuesday.
Dutch airline operator KLM, part of Air France-KLM, said on Monday night it had canceled 16 flights flying to and departing from four British cities and scheduled for Tuesday. Fights to and from Aberdeen, Glasgow, Edinburgh and Newcastle would be canceled on Tuesday morning, it said.
Iceland`s aviation authority reopened Keflavik airport late on Monday, but said it was impossible to know whether the island`s international hub would remain open on Tuesday.
"It is open now," spokeswoman Hjordis Gudmundsdottir said. "We will know tonight or tomorrow morning how it will go."
Last year, ash from an Icelandic volcano caused 100,000 flights to be canceled, stranding 10 million passengers and costing the industry an estimated $1.7 billion in lost revenue.
Asked earlier on Monday if the ash cloud would cause some disruption to flights this time, a spokesman for Britain`s Civil Aviation Authority said: "That`s the way it`s looking certainly at the moment."
Europe`s air traffic control organization said that if the volcanic emissions continued at the same rate, the cloud could reach western French and northern Spanish airspace on Thursday.
President Nicolas Sarkozy is due to host Obama and other G8 leaders in France later this week.
Authorities have backed more relaxed rules on flying through ash after being criticized for being too strict last time.
"I think the regulators are a bit more sensible than they were last year," Michael O`Leary, chief of budget airline Ryanair, told a conference call. "We would be cautiously optimistic that they won`t balls it up again this year."
Nevertheless, airline shares fell between 3 to 5 percent.
German Transport Minister Peter Ramsauer said he did not expect the Icelandic eruption to disrupt air traffic to the same degree as last year. But he added that there would be a flight ban for jet planes should particles from the ash cloud reach a concentration higher than 2 milligrams per cubic meter.
Speaking to Sky News, British Transport Secretary Philip Hammond said authorities could work with airlines to "enable them to fly around concentrations of ash rather than having to impose a blanket closure."
Grimsvotn erupted on Saturday and smoke funneled as high as 20 km (12 miles) into the sky. The eruption is the volcano`s most powerful since 1873 and stronger than the volcano that caused trouble last year.
But scientists say the type of ash being spat out is less easily dispersed and winds have so far been more favorable.
"The difference in impact on aviation comes down to three factors: the ash being produced by the eruption, the weather patterns blowing the ash around, and new rules about planes flying into ash," University of Edinburgh volcanologist John Stevenson wrote on his blog.
Smothered in ash
Some were expecting problems, however. "It`s too early to tell if Europe will be affected. What`s certain is that when it is affected, there will be flight cancellations," French Transport Minister Thierry Marianai told Europe 1radio.
Airlines as far away as Australia were monitoring the cloud. Norway`s civil aviation body said the one or two flights a day to the Arctic archipelago of Svalbard would shut Monday night. A small part of Greenland`s eastern air space was also closed.
The Icelandic Met Office said on Monday night the eruption had abated slightly since Sunday, with the ash cloud at 5-9 km elevation in the previous few hours. But it also said that volcanic activity remained strong and steady.
The volcano lies under the Vatnajokull glacier in southeast Iceland, the largest glacier in Europe. People living in districts close by have been smothered in ash.