Taoiseach Micheál Martin has said his "sense" is that a newly agreed €450,000 fund to pay secretarial supports for former presidents "may never in its entirety be drawn down".
RTÉ News reported on Thursday evening that the significant sum of money has been outlined under the Department of the Taoiseach's expenditure accounts.
While there is a long-established degree of confidentiality when it comes to spending in relation to Áras an Uachtaráin or costs for former presidents, it has been established that the €450,000 funding is a new arrangement and was put in place around the time of the change in president last October.
The funding is intended to pay for any secretarial supports for the three living former presidents of Ireland - Mary Robinson, Mary McAleese and Michael D Higgins.
This is similar to long-established secretarial supports for former taoisigh.
However, it is entirely unclear where the request for the new arrangement for former presidents originated.
The funding - which will be a recurring expense - is understood to be linked to the civil service grade of higher executive officer, which has a salary ceiling of €76,000 a year.
Asked if a Government department requested the funding or whether the request came from elsewhere, the Taoiseach said: "Well I think basically our sense is that... first of all that money may never in its entirety be drawn down, because I think we're looking at a fairly modest secretarial support, or administrative support for former presidents, if they choose to take that.
"Many of them as you know act internationally post-their presidency role because of their status and so on, and they contribute to international fora.
"They do a very good job actually of representing Ireland, and so we feel it's a reasonably modest response."
Aontú leader Peadar Tóibín told RTÉ News he intends to raise the matter in the Dáil in the coming days.
