Dublin  - Voting in Ireland's referendum on the European Union's Lisbon Treaty was set to get underway Monday on five islands off the north-western coast, three days before the rest of the country.

In total 745 people are entitled to vote on the islands off the coast of County Donegal. Arranmore, Gola, Inishbofin, Inishfree and Tory traditionally vote early in case bad weather cuts them off, delaying the collection of ballot boxes.

The islanders' votes will be taken by helicopter to the mainland and counted with the remainder of the Donegal constituency's votes on Friday.

The rest of Ireland votes Thursday on the treaty aimed at simplifying decision-making in the 27-member bloc. Polls show the result of the referendum is balanced on a knife-edge. (dpa)