As the ash cloud moves across northern Europe, UK flights resumed today but the cancellations spread to Germany, closing Hamburg and Bremen airports.

Airlines, including British Airways and easyJet, have slashed some German services as the ash cloud moved across Germany.

Despite the ash cloud from Icelandic volcano Grímsvötn clearing, for the most part, from UK skies, experts have warned that it may return on Friday, in time for the Bank Holiday weekend.

According to the Met Office, a high-density ash cloud will begin to affect southern England by Friday. However, rapidly changing weather makes it difficult to predict what impact the ash cloud will have over the next few days.

Flights across the UK were up and running today, following yesterday’s cancellation of a number of flights from Scotland and also from Newcastle airport due to high levels of ash.

Ryanair claims it’s safe to fly through ash cloud
Flights grounded in Scotland due to ash cloud

High-density areas of ash have been designated “red zones” by the Civil Aviation Authority (CAA), creating no-fly zones. However these have been questioned by both Ryanair and BA.

Yesterday, Ryanair boss Michael O’Leary said his airline had flown a test flight through a red zone in Scotland and found no evidence of volcanic ash.

O’Leary slammed the CAA and the Met Office, calling the red zone “mythical” and suggesting officials “take their finger out of their incompetent bureaucratic backsides and allow the aircraft back into the skies over Scotland”.

Now BA has also sent up a test plane to judge ash levels.

Willie Walsh, BA chief executive said the test plane flew in a red zone for 45 minutes and had “found nothing”.

Ryanair’s findings were yesterday dismissed by Transport Secretary Philip Hammond, who said that the airline had not actually flown into a “red zone”.

“Safety of passengers and aircraft is our number one priority and we will not be bullied by Mr O’Leary or anyone else from our safe approach,” he said.

However Hammond conceded that the BA flight had been CAA-authorised and the information gathered would now be studied.

Hammond said the ash cloud was expected to come back to the UK on Friday but it could be at such high altitude that planes will be able to fly beneath it.