Thousands face volcanic ash cloud flight cancellations

BA, KLM, Aer Lingus and Easyjet are among the airlines that have chosen to suspend services in and out of Scotland for the coming hours.

But Ryanair has objected to an order from Irish officials to ground its morning flights to and from Edinburgh, Glasgow and Aberdeen on safety grounds.

The ash cloud is not due to reach other parts of the UK until later on Tuesday.

The Met Office said the ash had already reached northern Scotland and would spread to Wales, northern England and Northern Ireland by midday and across much of the UK by the end of the day.

But forecasters said changing wind patterns make it hard to predict its exact path and concentrations would vary between regions.

Ryanair said it would complain about the "unnecessary cancellations" to the Irish Aviation Authority.

The cancellations come just over a year after another volcanic eruption in Iceland caused widespread disruption across Europe, including the closure of UK airspace, amid concerns about the damage volcanic ash could cause to engine aircraft.

This year, in the UK, the decision on whether to fly or not in ash cloud conditions is down to individual airlines, although they have to apply to the Civil Aviation Authority (CAA) for final approval.

The transport secretary said the UK was "better" prepared than it had been in 2010.

The Grimsvotn volcano in Vatnajokull National Park began erupting on Saturday.

Iceland's airspace has been closed for a period as a result but experts say this eruption is on a different scale to the one last year and ash particles are larger and, as a result, fall to the ground more quickly.

However, the threat of disruption saw US President Barack Obama arrive in the UK from the Republic of Ireland on Monday night, a day ahead of his scheduled arrival for his state visit.

Since last year, the CAA has graded ash levels as low, medium or high, and airlines are notified if levels reach medium or high.

All British aircraft can fly in medium-density ash but the airlines need to consider whether to fly, according to risk assessments.

A CAA spokesman said the current cloud could "potentially" cause serious disruption as charts showed the ash density below 35,000ft had reached the highest level at more than 4,000 microgrammes per cubic metre.

But he said procedures were "totally different" compared with last year and although no airlines had applied to fly in high-denisty ash, some had applied for, and been given, permission to fly in medium ash.