130 members of the Defence Forces are, for the second time in a year, unable to return home to their families tomorrow.
The troops are part of the UNDOF mission in the Golan Heights and were scheduled to fly out of Beirut and land in Dublin Airport at 9.40am tomorrow morning.
In the last hour, it has emerged that they will not be home as scheduled.
They have finished a six-month tour of duty and the soldiers to replace them have already arrived.
A spokesperson for the Department of Defence said: "The United Nations is responsible for organising the rotation flights to transport the current UNDOF contingent back to Ireland."
"We have been advised by the UN that the Lebanese Authorities have not yet granted approval of the landing clearance in Beirut for the aircraft scheduled to transport the 59th Infantry Group."
"At the request of Minister Paul Kehoe, Ireland's Permanent Mission in New York is engaging directly at the highest levels with the UN in New York, with a view to resolving the situation as quickly as possible."
"Defence Forces personnel remain at their base at Camp Faoar in Syria pending resolution of the situation."
"Families have been informed of this delay by designated Family Liaison Officers, and further updates will continue to be provided as they become available," the spokesperson added.
One wife, who did not want her name used, said: “Myself and the children are devastated, we have gone through a long arduous six months without him.”
“The kids were so excited about seeing their Dad in the morning and having to break the news to them was heartbreaking.
“I know we are in a lucky enough position living close to the airport but some families will have travelled from around the country today to be in Dublin to collect their husbands/dads/sons in the morning.”
“I’m also aware of a number of troops who have travel plans this weekend with their families.
"This is just another example today of the appalling treatment of our troops by the Taoiseach, Minister Kehoe and the pen pushers in the Department of Defence,” she added.
PDFORRA, which represents members of the Defence Forces, said it was "bitterly disappointed" to learn of the departure delay.
Mark Keane, President of PDFORRA said: “Our thoughts and concerns are with the personnel involved and their families.
"These troops were due to depart the Golan today and arrive home to meet with their families tomorrow. For such a hold up to emerge with two successive units is quite remarkable - and all those people affected need an immediate explanation”
Gerard Guinan, General Secretary of PDFORRA said: “It is difficult to understand how such a problem can have emerged again; surely lessons must have been learned with the delayed return of the 58th Battalion last October.
"A mistake in planning has surely been made either by the UN or here at home and those affected must get an explanation”