Senior ministers are likely to be given responsibility for portfolios such as Defence and the Gaeltacht in the next government should it get the green light from party members tomorrow, RTÉ News understands.
The leaders of Fine Gael, Fianna Fáil and the Green Party were due to meet to discuss the ministerial and departmental structure of that government.
It is likely too that the Department of Children will remain, but will have an additional role.
There had been calls during the programme for government negotiations for a standalone Department of Marine, but it is set to remain aligned with the Department of Agriculture.
The government would also have two super junior ministers along with the Chief Whip, all of whom would attend Cabinet meetings.
Amid reports that there could be up to 20 junior ministers, it has not been decided yet if they would be named on Saturday or some days later.
The Taoiseach has said there will be some reconfiguration of government departments to take the priorities of Fine Gael, Fianna Fáil and the Green Party into account.
Speaking this evening after a Cabinet meeting at Dublin Castle, Leo Varadkar said his prediction is that the three parties will vote tomorrow to enter a coalition and a new taoiseach to be elected by the Dáil on Saturday.
He said he believed the yes vote would be larger than predicted.
"There is no arrangement in place" for a Plan B or to have a temporary taoiseach elected if the programme for government is not accepted, he said.
The Cabinet meeting today was the final gathering of this Government, if the parties agree tomorrow to enter a coalition.
Mr Varadkar said some travel restrictions between Ireland and other countries will be eased from 9 July.
Minister for Health Simon Harris said that the wearing of face coverings on public transport will be made mandatory and there will be a sanction for non-compliance.
Taoiseach Leo Varadkar says serving as the country's Taoiseach has been the greatest honour of his life, during what may be his final press conference as leader. | Follow live updates: https://t.co/FEymVrmgjn pic.twitter.com/luGcl9Uwhh— RTÉ News (@rtenews) June 25, 2020
Mr Varadkar said that being Taoiseach for the last three years has been the "greatest honour" of his life.
He said he thinks he has "learned more in the last three months, than a lifetime in politics."
In relation to the Covid-19 outbreak, Mr Varadkar said: "I pray that our country never has to go through something like this again."
Taoiseach says he knows what role he'd like in the next government but it’s a jigsaw and it hasn’t come together yet @rtenews— Mícheál Lehane (@MichealLehane) June 25, 2020
Mr Varadkar said: "It is possible that this is my last press conference as your Taoiseach, and if so, I want to end by saying thank you to the men and women who kept our country protected and guided us through this emergency."
He also said he believes the country "owes a profound debt to the Chief Medical Officer Dr Tony Holohan, who has become one of the most trusted figures in the country and made us all feel that we were in safe hands."