Waves of Israeli air strikes are reported to have destroyed three highway bridges north of Beirut, forcing UN relief agencies to cancel several aid convoys.
The Israeli air force's bombing of bridges in the Christian heartlands north of the capital cut off the main coastal highway to Syria.
Separately, the Irish Red Cross is to deliver an urgent briefing on the growing humanitarian crisis to the Minister of State with responsibility for Overseas Development and Human Rights, Conor Lenihan.
With up to a million people now displaced by the ongoing conflict in Lebanon, the Irish Red Cross will outline to the minister what action the Red Cross is taking in the country and what further help is needed.
Of particular concern to the Red Cross is the disregard being shown to the Geneva Conventions, especially the fourth Geneva Convention concerning the protection of civilians and the safety of medical workers.