Sinn Fein members have been told Gerry Adams is a central part of the party's Irish government formation negotiating team.
In a Sinn Fein briefing note, Mr Adams is listed along with other unelected party members Martin Lynch, Dawn Doyle, Stephen McGlade and Ken O'Connell as part of the team.
Sinn Fein publicly announced that its negotiating team would be led by Pearse Doherty and include Eoin O Broin, Louise O'Reilly and Matt Carthy.
Mr Adams attended the ard comhairle meeting where the negotiating team was decided. However, his appointment to the team was not publicised.
A Sinn Fein spokesperson said: "Sinn Fein has many experienced negotiators and we will draw on that experience as required."
A source said Mr Adams has been involved in a negotiations for "most of his life" and this was why he is involved in the talks.
Mr Adams sat in the Dail's visitors' gallery in Leinster House during the vote for Taoiseach yesterday, along with other party supporters. He played a low-key role during the Irish election campaign but has been attending party events since the vote. Mr Adams (inset) resigned as Sinn Fein leader in 2017 and did not run for the Dail in the recent general election.
The 33rd Dail sat for the first time yesterday - 11 days after the outcome of the Irish election produced a different political landscape.
Fianna Fail TD Sean O Fearghail was re-elected as Ceann Comhairle (speaker) in the Dail after receiving 130 votes. During the first sitting, the Dail failed to elect a taoiseach.
Sinn Fein leader Mary Lou McDonald, Fianna Fail leader Micheal Martin, Fine Gael leader Leo Varadkar and Eamon Ryan were all nominated, but none emerged with a majority vote.
Ms McDonald emerged as the most popular candidate with 45 TDs backing her.
However, 84 TDs voted in opposition with 29 TDs abstaining.
Mr Varadkar secured 36 votes in favour of him as taoiseach, while 107 TDs voted against.
Mr Martin secured 41 votes in support, with 97 TDs against.
Mr Ryan received 12 votes in support and 115 in opposition.
Mr Varadkar will travel to the Aras an Uachtarain to resign from office, but will carry out his duties in a caretaker capacity until a new taoiseach is appointed.
He told the Dail: "The responsibility is on all of us to ensure we provide good government, and indeed good opposition.
"I think the onus is on those who have made enormous promises of change to the people during this election who are entrusted with that mandate to bring a programme of government for approval. If they cannot, they should say so and be upfront and honest about their failures and the empty promises they made."
He said he will travel to Washington DC for the traditional St Patrick's Day events.