Volcanic Ash from Iceland continues to cause disruption

The UK is enduring a fourth day as a virtual no-fly zone, as the travel chaos caused by volcanic ash drifting from Iceland shows no sign of ending.

Flight restrictions have been extended until at least 7pm and forecasters say the ash cloud could remain over the UK for several more days.

BBC business editor Robert Peston said the disruption risked becoming a "major business and economic disaster".

He said a number of European airlines were facing financial difficulties.

Our correspondent said: "If [the disruption] goes on many days longer, a number of European airlines will run into financial difficulties and may need bailing out by governments - or so I am told by senior airline figures."

On Friday, the International Air Transport Association (IATA) warned airlines would lose at least $200m (£130m) per day in revenues during the disruption.

Meanwhile, Dutch airline KLM and German airline Lufthansa have carried out test flights in their countries' airspace to see if it is safe for planes to fly.

KLM said its aircraft had been able to fly at its normal operating altitude of 13km (8 miles) over Dutch skies and no problems had been reported. The plane's engines were being inspected for possible damage, with a view to getting permission from the aviation authorities to start up operations again.

The disruption has affected hundreds of thousands of travellers since Wednesday, when the Eyjafjallajoekull volcano began erupting.

Among those affected were British wedding guests who had to watch on an internet connection as a bride and groom stranded in Dubai took their vows.

Link to live webcam of the volcano

The silver lining?

In the shadow of the volcano

Eruption at Mayon Volcano imminent say experts

The Mayon volcano in the Philippines, which has blown its top nearly 40 times in 400 years, menaced nearby residents with small eruptions of ash and lava on Wednesday as Philippine authorities moved more than 30,000 people to shelters in case of a larger eruption.
Trickles of lava rolled down the 8,070-foot mountain towering over the Albay Gulf in the central Philippines, while five new ash explosions, one of them reaching 550 yards in the air, shook Mayon's steep slopes.
During the day, the summit (the top of the volcano) is shrouded in white clouds of dust and ash, and dark orange lava becomes clearly visible in the nighttime. Residents of Legazpi city on the foothills of the cone-shaped mountain converge in a downtown park at night to watch the spectacle from a safe distance.

Look to the left to see video footage of the volcano

Philippine volcano fears force thousands to evacuate

More than 20,000 people have evacuated homes in the Philippines after lava and ash flowed from one of the nation's most active volcanoes.
Soldiers and police directed the evacuation from around the foothills of Mayon volcano amid concerns that a big eruption could occur at any moment.
Philippine officials raised the alert level for Mayon on Monday.
Mayon, 330km (206 miles) south-east of the capital Manila, has erupted 48 times since records began.
The head of the disaster relief operations in the region, Cedric Daep, said the authorities aimed to evacuate nearly 50,000 people from villages within eight kilometres of the volcano by Thursday.

In pictures: Filipinos flee
He said that after a series of ash puffs and ash explosions up to 1,000m high, a major explosion could not be ruled out.