Flights out of Irish airports may have resumed after being cancelled earlier today but aviation chiefs have warned of further travel problems in the coming days.

Flights to and from the country were postponed up to 1pm this afternoon because of an ash cloud drifting over the country from Iceland. Over-flights of Ireland from the UK and Europe were unaffected by the flight ban because ash concentrations do not affect the airspace above 20,000 feet.

Air space over Scotland, Northern Ireland is to close from 7am tomorrow morning due to ash, it was confirmed tonight. The Irish Aviation Authority is due to release a statement at about midnight.

The IAA last night decided to impose a "no-fly zone" over Ireland from 7am under advice from the Volcanic Ash Advice Centre in London that there was a risk of "ash ingestion" to aircraft engines.



The decision was based on the safety risks to crews and passengers and followed a change in the weather resulting in the ash cloud being pushed south over the country by northerly winds. Ireland and Scotland are the only countries affected.



However, the authority this morning said it had cleared Irish airports to open for "full operations" from 1pm.

The UK’s Civil Aviation Authority (CAA) said airspace over Northern Ireland could also reopen at 1pm, allowing flights to resume from Belfast City, Belfast International and City of Derry airports.

The majority of flight arrivals at Irish airports did not resume until late this afternoon, with most arrivals at Dublin airport cancelled up to 3.45pm.



All flight arrivals at Cork Airport, with the exception of Aer Arann flight RE295P from Dublin, were cancelled up to 3.55pm.



A spokeswoman for Ryanair said it was operating a number of extra flights between Dublin and Stansted, Faro, Seville and Fuerteventura during the afternoon to repatriate stranded passengers. The airline also said that gaps in capacity would help to accommodate passengers further.

The relief experienced by airline passengers could prove short-lived, with forecasters predicting more ash from the Icelandic volcano will blow down over the country later this week.

In a statement this morning, the authority said its decision to close airports earlier today was based solely on the safety risks to crews and passengers as a result of the drift south of the volcanic ash cloud caused by the north easterly winds. "The situation will be reviewed as the week goes on. Winds are forecast to continue coming from a Northerly direction for the next few days and this could lead to further problems," it said.



Speaking to The Irish Times, Met Éireann forecaster Evelyn Cusack warned that airflow would remain northwesterly for the rest of today, tonight and tomorrow, increasing the risk of further ash disruption.



However, she said the risk of ash disruption would be lowered from Thursday onwards due to a shift in winds, with airflow changing to a northeasterly direction.

Elsewhere, Irish Airport Authority (IAA) chief executive Eamon Brennan forecast months of uncertainty as a result of the volcanic ash cloud.



“We’re not out of the woods yet,” he told RTÉ radio.



“There’s no doubt about it, we’re probably facing a summer of uncertainly due

to this ash cloud," he added.

Meanwhile, Minister for Transport, Noel Dempsey, who was also affected by the travel problems said today, a strong European response is needed to deal with the continuing disruption to flights as a result of ash cloud from the Eyjafjalljökull volcano.

Welcoming the outcome of a meeting of EU Transport Ministers this morning, Mr Dempsey said an action plan was necessary to deal with the situation as it continues to evolve.

Mr Dempsey, who was unable to travel to the meeting due to the closure of Irish airspace, said: "Safety is at the heart of Europe's response and it was appropriate that a significant part of the discussion this morning focussed on the development of appropriate risk assessment methodologies to deal with potential future threats".

Today's flight cancellations were due to the first closure of Irish airspace since restrictions were lifted on April 20th following six days of suspension. That closure led tothe cancellation of 100,000 flights internationally, and disruption to about 10 million passengers. The crisis is estimated to have cost the air transport industry up to €2.5 billion.

The Dublin Airport Authority estimated it lost €7-8 million as a result of the cancellation of 3,200 flights, affecting 400,000 passengers, during the previous shutdown.

The IAA this afternoon said it will continue to monitor the movement of volcanic ash, and would issue a further update at 0900 hours on tomorrow.