Volcanic ash cloud gets bigger as travel chaos grows

• Smoking: gases pour from the volcano in southern Iceland's Eyjafjallajokull glacier. A lingering volcanic ash plume forced extended no-fly restrictions over much of Europe yesterday. Picture: Getty

Scientists warned last night the volcano appeared to be becoming more active and weather patterns suggested the cloud was unlikely to be dispersed until the end of this week.

Yesterday, the huge cloud of volcanic ash, which can clog jet engines, spread south-east across the continent, halting more than three in four flights and stranding up to two million passengers worldwide.

European aviation agency Eurocontrol said no landings or take-offs were possible for civilian aircraft in most of northern and central Europe because of the ash from the still-erupting volcano. As more airlines, including British Airways, cancelled both long and short-haul flights, air traffic controllers closed UK airspace until 1pm this afternoon.

Meanwhile test flights are taking place in the Netherlands and other European countries to assess the impact of volcanic ash on plane parts A Dutch ministry spokeswoman said the flights were taking place at lower altitude than usual.

Experts said the effects of the plume, which by midnight last night was covering most of western Europe, would be felt for an extensive period of time.

Icelandic authorities announced that the volcano was still belching out ash.

"The ash will continue to be directed towards Britain and Scandinavia," Teitur Arason, of the Icelandic Meteorological Office, said yesterday.

Geologists said Eyjafjallajokull's eruption was gathering pace. "The activity has been quite vigorous overnight, causing the eruption column to grow," said volcano expert Magnus Tumi Gudmundsson. "It's the magma mixing with the water that creates the explosivity. Unfortunately, there doesn't seem to be an end in sight."

Graeme Leitch, a meteorologist at Britain's National Weather Service, said: "Currently the UK and much of Europe is under the influence of high pressure, which means winds are relatively light and the dispersal of the cloud is slow. We don't expect a great deal of change over the next few days."

Scottish airports reopened briefly on Friday as winds blew the ash away from the country. But, after the arrival of four transatlantic flights, they closed again yesterday morning and BAA, the country's biggest airport operator, told passengers not to come for their flights.

Airports in places as far apart as Iceland and the Crimean peninsula on the Black Sea were shut.

Plans by world leaders and dignitaries to attend today's state funeral for Polish president Lech Kaczynski and his wife Maria in the southern city of Krakow were also affected. Prince Charles will not attend, Clarence House said last night, while Foreign Secretary David Miliband also cancelled. US President Barack Obama, German Chancellor Angela Merkel and Canadian Prime Minister Stephen Harper also said last night they would not take part in the funeral.

The chaos extended beyond Europe. Hotels in Beijing and Singapore said they were running out of rooms for Europeans unable to return home.

Ferry and train operators in Europe were yesterday continuing to try to replace air services – but ticket prices have risen. Taxi drivers reported taking fares worth thousands of pounds to move stranded travellers.