The United Nations Convention on the Law of Treaties was done at Vienna on 23 May 1969 and entered into force on 27 January 1980.
Ireland does propose to accede to the convention, but further consideration of its terms will be necessary due to their complexity. To this end, a detailed study of the terms of the convention is currently ongoing within my Department, which I hope will conclude shortly. Upon receipt of this study, I propose to put the question of accession before the Government.
I should point out that many provisions of the convention merely codify existing rules of customary international law by which Ireland is already bound in its treaty relations with other states. This explains why accession to the convention, although desirable, has not in the past been considered a matter of priority or urgency. I am satisfied that while it is preferable that Ireland should in due course become party to the Vienna Convention on the Law of Treaties, our international relations are not adversely affected by the fact that we have yet to accede to it.