Updated:
The chaos in air services over Northern Europe witnessed today is expected to continue at least throughout the morning tomorrow (Friday) after forecasters predicted that a cloud of fine volcanic ash from an Icelandic volcano would linger over Northern Europe and drift south.
UK air traffic control said British airspace would remain closed at least till noon on Friday. Belgium, Finland, Holland Norway and Denmark also said their air space would be closed and Germany said its Northern airports, including Berlin, would close.
Up to half of transatlantic flights are expected to be affected.
13 flights to and from Malta were affected.
Air Malta said this evening that it will provide extra flights to London, Manchester and Birmingham tomorrow if conditions allow. The airline was forced to cancel its afternoon flights to and from Manchester, Birmingham, Heathrow, Gatwick, Brussels and Moscow but the morning flights to Healthrow and Gatwick were operated normally.
EasyJet and Ryanair also cancelled their flights from various UK airports to Malta as well as from Stockholm and Dublin, with hundreds of passengers being standed.
Air Malta said clients due to travel from Malta International Airport should contact flight enquiries tel: 5004 3333 for further information and to confirm flight arrival or departure times.
For re-booking or re-routing, clients should contact Air Malta’s International Call Centre tel: 356 2166 2211.
Subject to the lifting of airport restrictions, Air Malta will tomorrow operate an extra flights to Gatiwick (dep Malta 7 a.m. dep Gatwick 11.05 a.m.) and Manchester (dep Malta 3 p.m., dep Manchester 7.25 p.m.)
Air Malta is also planning to operate two other extra flights to London Heathrow and Birmingham.
However, weather experts said the fallout from the Eyjafjallajokull volcano in southeast Iceland could take several days to clear.
With thousands stranded in airports around the world, Eurocontrol, the European air traffic control group, said planes would stay grounded for at least 48 hours.
It estimated between 4,000 and 5,000 flights were affected today (Thursday) as grey ash from the second major eruption in Iceland in less than a month blew across the Atlantic, closing major airports more than 1,000 miles (1,700 kilometres) away.
Belgium, Britain, Denmark, the Netherlands, Norway and Sweden all shut down their airspace because the ash was a threat to jet engines and visibility. There was also major disruption in Finland, France, Germany and Spain.
Norwegian Transport Minister Magnhild Meltveit Kleppa said the "airspace will be closed tomorrow (Friday) too, and the outlook for the next two-three days is not good".
Hundreds of flights out of London's Heathrow and Gatwick airports were cancelled, including transatlantic services. Scandinavian airline SAS said it had cancelled 635 flights alone.
Flights heading for Europe were stacked up all around the world. Norwegian Prime Minister Jens Stoltenberg was stranded in New York, the NTB news agency reported.
British Airways said it would run no flights in or out of Britain until at least Friday morning. Amsterdam's Schiphol airport prepared beds and meals for stranded travellers.
"The cloud of volcanic ash is now spread across the UK and continuing to travel south," said the National Air Traffic Services, which manages British airspace.
"In line with international civil aviation policy, no flights other than agreed emergencies are currently permitted in UK controlled airspace," it said, grounding all non-emergency flights until 0600 GMT Friday.
The ash drifted at an altitude of about 5.0-6.0 miles (8.0-10 kilometers) and could not been seen from the ground. But experts said it posed a major threat to air traffic.
In the past 20 years, there have been 80 recorded encounters between aircraft and volcanic clouds, causing the near-loss of two Boeing 747s with almost 500 people on board and damage to 20 other planes, experts said.
The prevailing winds meant that Icelandic airports remained open.
"Flights to and from Iceland are still OK. The wind is blowing the ash to the east," Hjordis Gudmundsdottir of the Icelandic Airport Authority told AFP.
The volcano on the Eyjafjallajokull glacier in southern Iceland erupted just after midnight on Wednesday.
Smoke from the top crater stacked more than 20,000 feet (6,000 metres) into the sky, meteorologists said. A 500-metre fissure appeared at the top of the crater on Wednesday, Iceland's RUV broadcaster said.
The heat melted the surrounding glacier, causing major flooding which forced the evacuation of between 700 and 800 people to Red Cross centres.
Last month, the first volcano eruption at the Eyjafjallajokull glacier since 1823 -- and Iceland's first since 2004 -- briefly forced 600 people from their homes in the same area.
That eruption at the Fimmvorduhals volcano, which gushed lava for weeks, ended Tuesday, experts said.