A representative from RTE has met with Sinn Féin regarding the Prime Time debate on Tuesday.
The party's director of elections Pearse Doherty raised the issue of Mary Lou McDonald being involved in the meeting, which took place earlier today.
A meeting of RTE's election committee will be held tomorrow morning.
Speaking earlier today, Taoiseach Leo Varadkar suggested that Mary Lou McDonald should be involved tomorrow.
"As I've said before and I'll say again, I've no objection to Mary Lou McDonald taking part in the debates, and that is a matter for the broadcaster," he said.
"I think it'll be useful to take an opportunity to scrutinise Sinn Féin's policies a bit more," he added.
In a statement issued today, the broadcaster said: “At the outset of the election RTÉ set out its approach to leaders debates based on empirical data. That has not changed."
"Throughout the campaign RTÉ has considered representations made by those contesting the election regarding our coverage and leaders debates. We will continue to give consideration to any representation made.”
“A representative of RTÉ met with Sinn Fein today and the broadcaster will respond to the issues raised in due course,” it added.
It's after a Red C poll for today's Business Post put Fianna Fáil and Sinn Féin in joint first place on 24 per cent.
Sinn Féin has surged five points, with Fianna Fáil and Fine Gael both down.
The Green Party stands at 7%, the Labour party on 5%, and the Social Democrats are at 3%.
Independent candidates have 12%.
The poll was carried out over seven days up to Thursday.
With reporting by Andrew Lowth.