Update 10.38pm: Taoiseach Leo Varadkar has led a strong defence of the Tanaiste at the emergency Fine Gael meeting tonight in Leinster House.
The meeting voted unanimously to support the Tánaiste-after calls for her to go over the mishandling of the Maurice McCabe email saga.
Mr Varadkar told the gathering the Tánaiste was facing a "trumped up charge from the opposition".
Afterwards, Fine Gael's parliamentary party chairman Martin Heydon said: "What we have seen from both Sinn Féin and Fianna Fáil today is a political stunt, pure and simple. We will not allow the opposition to bully us.
"Sinn Féin is attempting to undermine the work of the Charleton Tribunal which was set up by the Fine Gael-led Government to investigate the treatment of Maurice McCabe and get to the bottom of whether or not there was a campaign against him - the same Charleton Tribunal that the opposition agreed to in the first place.
"History shows that Fine Gael adheres to due process and has respect for natural justice.
"Fine Gael stands fully and united behind the Tánaiste and Minister for Enterprise and Innovation, Frances Fitzgerald."
Update 9.52pm: Housing Minister Eoghan Murphy has said that the government is standing behind Tanaiste Frances Fitzgerald, as the threat of a general election looms tonight, writes Juno McEnroe.
The minister, who effectively ran the successful campaign to get Leo Varadkar promoted to Taoiseach, said the public would not understand why there would be an election.
His defence of the Tanaiste came amid a tense standoff between Fianna Fail and the Fine Gael government tonight over the position of Ms Fitzgerald and criticism how she handled an email that revealed a garda management strategy to discredit whistleblower Maurice McCabe.
Minister Murphy told RTÉ Prime Time tonight that if Fianna Fail collapsed the confidence and supply agreement, that the government would be forced into a general election without the public understanding why.
Asked when there might be an election and if it could be delayed, the minister said there was outstanding work on housing and other matters that the government wanted to get done.
“We are going to stand behind the Tánaiste because she acted appropriately and done nothing wrong,” added Mr Murphy.
Update 9.21pm: Taoiseach Leo Varadkar has called a one-issue emergency Fine Gael meeting of TDs and senators for 10pm tonight in which he will say the party and Government must continue to support crisis-hit Tánaiste Frances Fitzgerald, writes Fiachra Ó Cionnaith.
Mr Varadkar called the meeting this evening after Fianna Fáil justice spokesperson Jim O'Callaghan warned his party no longer has support in the under-pressure Tánaiste and will put down a no confidence motion next week if she is not removed from her position.
It is expected Mr Varadkar will tonight tell the Fine Gael parliamentary party meeting that he is 100% backing Ms Fitzgerald and will not give in to Fianna Fáil.
During the one-issue meeting the Taoiseach will also call for all TDs and senators to continue to support the Tánaiste, with the view to be repeated in broadcast appearances by Rural Affairs Minister Michael Ring and Housing Minister Eoghan Murphy.
The decision by Mr Varadkar to effectively call Fianna Fáil's bluff and insist he will not remove Ms Fitzgerald means Fianna Fáil is certain to publish its no confidence motion for next week on Friday morning.
This move, and the highly likely event that the motion will be passed by the Dáil, means the confidence and supply deal is now set to be torn apart - a situation that unless immediately rectified will cause a Christmas general election.
Update 7pm: Fianna Fáil has said it no longer has confidence in Tánaiste Frances Fitzgerald and said she should resign her position, writes Daniel McConnell.
The decision of the party, which is propping up the Government, places pressure on Ms Fitzgerald to resign or for the Taoiseach Leo Varadkar to sack her to avoid a General Election.
The party's spokesperson on Justice and Equality Jim O'Callaghan has said Fianna Fáil is considering tabling its own motion of no confidence in Ms Fitzgerald, but called on the Taoiseach to act now to stop a General Election from occuring on this issue.
Speaking this evening, Mr O'Callaghan said the events of recent weeks relating to the Maurice McCabe email saga meant her position is no longer tenable and she should step down.
This afternoon, ministers were rallying behind Ms Fitzgerald and said they would robustly fight any motion of no confidence, but the decision of Fianna Fail to withdraw confidence in her is highly significant.
Mr O'Callaghan, speaking on RTE News, said that his party leader Micheal Martin and Mr Varadkar spoke on Wednesday and it was made clear that Fianna Fail no longer had confidence in the Tanaiste.
He said that the Confidence and Supply agreement has been undermined by the events of the past week and that Fianna Fáil no longer has confidence in the Tanaiste.
When asked if Fianna Fáil was now backing the proposed Sinn Fein motion of no confidence, Mr O'Callaghan said there will be a vote of confidence in the Tanaiste adding his party may table such a motion by Friday morning, as his party's has private members time before Sinn Fein does.
Update 6.37pm: Health Minister Simon Harris said the Government has full confidence in Frances Fitzgerald after almost a week of controversy surrounding an email she received regarding Maurice McCabe in 2015.
Meanwhile, Sinn Féin said it is not trying to force an election by tabling a motion of no confidence in the Tánaiste next Wednesday.
But Sinn Féin’s Donnchadh O’Laoghaire said the Taoiseach could just sack Minister Fitzgerald.
"We're not trying to precipitate a General Election and this can be avoided. This can be avoided if the Tánaiste does the right thing, or if the Government intervenes itself," he said.
"Sinn Féin is ready for a General Election, we have always been ready for a General Election due to the nature of this Dáil. The make-up of it requires that we are always prepared and we are not fearful of a General Election. We're merely trying to enforce political accountability," he said.
Update 3.23pm: Health Minister Simon Harris has said the Government has full confidence in the Tánaiste after Sinn Fein put down a motion of no confidence in Frances Fitzgerald.
It follows almost a week of controversy surrounding the former Justice Minister over her handling of an email about Maurice McCabe in 2015.
The Health Minister said Sinn Féin’s motion is a political stunt to undermine the work of the Charleton Tribunal which is examining the whistleblower controversy.
"The Government has full confidence in Frances Fitzgerald as Tánaiste, as Minister for Business and on her time as Minister for Justice," he said.
"Obviously, it is a matter for every member of the Oireachtas to decide how they vote on any motion but we have a confidence and supply agreement with Fianna Fáil," he said.
"We have been doing our best to deliver for the people of Ireland through that agreement and Fianna Fáil have been doing their best to advance their policy priorities in relation that.
"The agreement is working and I expect the agreement to continue," he added.
Update 1pm: The Tánaiste has strongly denied claims in the Dáil that she tried to suppress an email which detailed a legal strategy to discredit garda whistleblower Maurice McCabe, writes Irish Examiner political reporter Elaine Loughlin.
Her denials have not prevented Sinn Fein proceeding with a motion of no confidence this afternoon, however.
The party's justice spokesman has confirmed the motion has been submitted to the Journal Office and is due to be taken next Wednesday
A motion of no confidence in Tánaiste Frances Fitzgerald has been submitted to Journal Office, and is due to be taken next Wednesday— Donnchadh Ó Laoghaire (@Donnchadhol) November 23, 2017
Frances Fitzgerald was forced to defend herself after coming under sustained opposition grilling in the Dáil this afternoon.
Ms Fitzgerald told the Dáil that she received an email last Thursday detailing the legal campaign taken by An Garda Síochána at the O'Higgins Commission. This email was first sent to her in 2015.
Fianna Fail spokesman Jim O'Callaghan asked why she had not passed on this email to the Taoiseah until Monday of this week. This was the same day as the information about the 2015 email was reported on RTE's Primetime programme.
Ms Fitzgerald said: "I want to be absolutely clear that the first time I knew about the email was last Thursday.
"That was the first time I heard that this email existed. The very first time."
However, Ms Fitzgerald failed to provide an answer on why she had not passed details of the email on to the Taoiseach for four days.
Sinn Féin Deputy leader Mary-Lou McDonald said the Tánaiste had "refused to provide clear answers and explanations".
She accused the Tánaiste of standing "idly by" when she was first sent the email and said the explanation given by Ms Fitzgerald that didn't remember receiving the email back in 2015 was "frankly not believable".
Ms McDonald added that this wasn't some "minor episode" that could be simply brushed away.
"It seems to me that there was a conspiracy to ruin this honorable man," Ms Donald told the Dáil adding that the email had shown a plan to discredit Sgt McCabe in the "worst possible way".
Ms Fitzgerald responded to Ms McDonald stating she wouldn't "take a lecture from you in due process and fairness".
"I am not trying to hide anything, I was not part of any conspiracy," she told the Dáil.
Update 12.35pm: Tánaiste denies any suggestion attempts were made to suppress email
Tánaiste Frances Fitzgerald has denied any suggestions that attempts were made to suppress an email linked to the Maurice McCabe controversy.
She said: No efforts have been made to suppress that email by me."
Sinn Féin Deputy Mary Lou McDonald asked Minister Fitzgerald: "Can you give an account for your failures?"
To which the Tánaiste responded: "I have been providing answers, I am not trying to hide anything, I was not part of any conspiracy to smear Maurice McCabe.
Deputy McDonald continued: "You failed to act, you failed to offer when it mattered, any protection to Maurice McCabe, you had sight and knowledge of this malicious strategy."
"You picked your side and you certainly weren't on Maurice's side.
"You failed as Minister for Justice, you failed Maurice Mc Cabe and it is now abundantly clear Tánaiste, that it is time for you to go."
Earlier: Frances Fitzgerald will be fighting to save her position when she takes Leaders’ Questions in the Dáil shortly.
You can watch the leaders' questions live from the Dáil here.
Sinn Féin has said it will table a motion of no confidence in the Tánaiste, unless she answers questions about her handling of the latest Maurice McCabe controversy to the party’s satisfaction.
Fianna Fáil TDs have indicated they might back Sinn Fein in that instance.
In particular, opposition TDs have queried the decision of the then Justice Minister not to act upon an email she got in May 2015 which mentioned a strategy to discredit Sergeant McCabe.
Minister Fitzgerald told the Seanad last night she had fresh legal advice which confirmed she should not interfere in the O’Higgins Inquiry.
Earlier: Sinn Féin to decide whether to declare no confidence in Tánaiste
Sinn Féin say they will wait until this afternoon to decide whether to declare no confidence in the Tanaiste.
The party says Frances Fitzgerald still has questions to answer regarding the Maurice McCabe controversy and expects her to answer them during leaders’ questions this afternoon.
Last night, Minister Fitzgerald said she had received fresh legal advice that her course of action, not to interfere in the O’Higgins inquiry, was the right one.
But Sinn Féin Senator Niall O’Dhonnghaile said she hadn’t done enough for whistleblowers.
He said: "You tell us again in your opening remarks, everything you have done in your ten years as minister for whistleblowers, but upon reflection, upon looking at the facts put before us, what did you do for whistleblowers in this particular incidence?
"Would you now like to revisit your memory when you have the opportunity here in the Seanad and correct these contradictory accounts on the floor."
Since Monday night, Frances Fitzgerald has faced mounting pressure to answer questions on her handling of an email sent to her in May 2015 – about a garda strategy to discredit Maurice McCabe.
On Tuesday and Wednesday, the Tanaiste was grilled about the controversy, first in the Dáil, and last night in the Seanad.
O’Donnghaile says there are still outstanding issues.
Labour say they will support a Sinn Féin motion of no confidence, while Fianna Fail have also said they will give the Tánaiste more time, but could support Sinn Féin, which would leave Leo Varadkar in a very difficult position regarding his deputy.
TD Dara Calleary says they are waiting until after question time to decide what to do.
He said: "We will access it following that, just remember Maurice McCabe and his family are at the heart of this and they need to be given justice."