Irish troops will begin their fourth mission to the Lebanon as peacekeepers next month.
Defence Minister Alan Shatter yesterday secured Dail approval for the deployment of 440 soldiers to the UN force in the Middle East.
It was the third element of the so-called Triple Lock procedure, involving UN, government and Dail approval before Irish troops could be sent abroad.
About 90 troops will leave on May 23 to set up the base camp in southern Lebanon for the main contingent, which will be deployed towards the end of June.
Mr Shatter said: "It is vitally important for Ireland to maintain a level of commitment to international peacekeeping operations and the obligations it has assumed through its membership of the UN."