The Irish Aviation Authority said it would allow flights to resume from all Irish airports from 1200 GMT on Tuesday but volcanic ash could bring more disruptions later in the week and periodically throughout the summer.
The IAA had closed airports from 0600 GMT until 1200 GMT due to risk of ash ingestion in aircraft engines, although overflights of Ireland from Britain and continental Europe had not been banned.
"The situation will be reviewed as the week goes on," the IAA said in a statement on Tuesday.
Continued northerly winds forecast for the coming days could bring more clouds of volcanic ash from an Icelandic eruption and disruption for passengers this week, it said.
"We could be faced with this periodically during the summer," IAA Chief Executive Eamonn Brennan added in an interview with public broadcaster RTE's radio news. "We are probably facing a summer of uncertainty due to this ash cloud."
Earlier on Tuesday, former state airline Aer Lingus said last month's closures lasting several days cut its earnings by about 20 million euros ($27 million), with the final bill dependent on the impact on passengers' longer-term travel plans.
ReutersLast Mod: 04 Mayıs 2010, 16:34