Fifty members of the Irish Army's elite Ranger Wing are due to leave for Chad tonight after weeks of delays.
The mission has been delayed twice over a lack of medical and logistical resources, and more recently because the rebel advance on the capital N'djamena closed the main airport.
The main contingent of 400 Irish troops is due to be in place in Chad in mid-May as part of the 3,700-strong EUfor peacekeeping force. They will protect refugees in Chad and those displaced by the conflict in Darfur in western Sudan.
About 200 EU troops, including eight Irish soldiers, are already on the ground, having arrived prior to the rebel offensive.
Representatives of the Chadian rebel alliance warned last week Irish troops will be considered a hostile force if they deploy alongside French forces.
On their arrival, the Rangers face a difficult 900km journey by land across Chad's arid interior to the eastern regions of Abeche and Goz Beida. About 400,000 refugees from Sudan's war-torn Darfur region are crammed into camps along the border.
Deployment of the 14-nation EU force began last week with Swedish Special Forces and French logistical units arriving at the reopened N'Djamena airport.
Lieut Gen Pat Nash, the Paris-based Irish commander of EUfor said an information campaign aimed at explaining the role of Eufor was already under way in Chad.
The Irish Anti-War Movement will hold a protest outside the Dáil this afternoon over the deployment. It claims the Irish Army is helping support "a French colonial adventure to prop up the corrupt undemocratic regime" of Chad's President Idriss Déby. It also accuses Ireland of taking sides in a proxy war that is raging between Sudan and Chad.
"It is utterly wrong and contrary to Ireland's tradition of military neutrality to put Irish troops in harms way by sending them into this situation," said IAWM chairman Richard Boyd Barrett. "The Government is putting the lives of Irish troops at risk to serve the interests of French colonialism and a corrupt and undemocratic regime."
There were heated exchanges in the Dáil yesterday as Minister for Defence Willie O'Dea accused Fine Gael backbencher John Deasy of being a liar and of misleading the house in a row over the transport of Irish Defence Forces to Chad.