Irish airspace will remain closed until at least 1pm tomorrow and travel disruption is likely to continue all this week, the Government's taskforce on emergency planning said this afternoon.
Ryanair today said it had decided to cancel all flight departures for northern Europe until 1pm on Wednesday.
The flight cancellations apply to; Ireland, UK, Denmark, Finland, Norway, Sweden, Belgium, Holland, France, Germany, Poland and the Baltic States.
"We have decided this afternoon to cancel all flights in northern Europe until at least lunchtime on
Wednesday," Ryanair chief executive Michael O'Leary told Sky News. "There is no indication this volcanic ash is going to clear under the present weather from Ireland, the UK, Scandinavia or northern Europe."
Met Éireann's Evelyn Cusack said today the forecast remained unchanged until Friday, when rain and south-westerly winds were expected. This would help to improve the airflow and should have an impact on the volcanic ash plume.
Maurice Mullen of the Department of Transport said the taskforce recognised the inconvenience to travellers stranded abroad and to visitors who have been delayed here and encouraged people to keep in contact with their air carrier or travel agent for updates.
He said Irish embassies and consulates were reporting increased inquiries from Irish citizens stranded overseas and this was expected to continue.
Mr Mullen said the Department of Foreign Affairs was offering assistance to "hardship cases" particularly those with mobility problems. He encouraged people to think of alternative means of travel such as ferry travel. He said the task force was asking ferry companies to review the capacity in the light of any increased demands being made.
He also said that the amount of ash likely to come to ground was "minimal, if any", and the impact on health would be equally minimal.
However people with respiratory conditions should have their medication with them at all times, Mr Mullen added.
He said the HSE had confirmed that requests for air ambulance services were being dealt with on a case-by-case basis, in consultation with the Department of Defence and the Irish Aviation Authority (IAA).
Mr Mullen said the Department of Enterprise, Trade and Employment was consulting with representatives of businesses that use air freight.
He said 98 per cent of volume of trade to and from Ireland was carried by ship and there was no evidence of any disruption to this.
The remaining two per cent of trade involved high value trade such as pharmaceutical goods and the information technology sector, he said.
The taskforce will meet again tomorrow at 10am.
The IAA has closed Irish airspace until 1pm tomorrow and said that "no commercial passenger flights, including North American traffic, will operate from any Irish airport during this period”.
“Met experts are predicting that the prevailing weather conditions will continue in the coming days,” said an IAA spokesman. “Ongoing restrictions are therefore likely.” The ban includes all transatlantic flights.
A spokeswoman for Dublin airport asked passengers not to come to the airport and instead to contact their airline.
In Northern Ireland and the rest of Britain flight restrictions have been extended until 6am tomorrow.
Aer Lingus has cancelled all UK, European and US flights scheduled to depart Dublin, Cork, Shannon, Belfast, London Heathrow and Gatwick tomorrow, including all regional flights.
The ash cloud has forced President Mary McAleese to cancel plans to fly to Poland for today’s State funeral of president Lech Kaczynski. The Air Corps said the conditions made it impossible to travel to Krakow for the ceremony.
No landings or takeoffs were possible for civilian aircraft in most of northern and central Europe yesterday, but flights were taking place in southern Europe, including Spain, the southern Balkans, southern Italy, Bulgaria, Greece and Turkey.
The World Health Organisation has said the particulate matter in the ash did not pose a health hazard so long as it remained in the upper atmosphere.
When ash enters the lower atmosphere in high concentrations, people with chronic respiratory conditions such as asthma, emphysema or bronchitis could suffer irritation, the WHO said.
It advised people to go indoors if they noticed irritation in their throat and lungs, a runny nose or itchy eyes.