The Irish Aviation Authority has closed the country's airspace until 6pm this evening following a increase in ash coverage over the country.
No commercial passenger flights including North American traffic will operate from any Irish airport during the period.
“The ash from the volcano is now being emitted to a higher level and thus the area of coverage and risk to aircraft has increased,” said an Irish Aviation Authority (IAA) spokesman.
The ban includes all transatlantic flights operating from any Irish airport.
“Similar types of restrictions are enforced in northern and central Europe as well as the UK,” said the spokesman.
The IAA made the decision based on the latest forecast from the Volcanic Ash Centre in London which shows a risk to Ireland from the Icelandic volcanic plume.
Many countries across Europe have made similar decisions leading to a third day of disruption for air travellers.
Ryanair has cancelled all flights into and out of Ireland, including internal flights until 1pm on Monday.
A further update is expected at 12.30pm today.