Reports of a major political announcement emerged on Wednesday morning, and at 12pm, Leo Varadkar confirmed he would be standing down as Taoiseach and Fine Gael leader.
His party is set to elect a new leader at its Ard Fheis in April, and the selection will then have to go to a Dáil vote to become the next taoiseach.
The timing is seen as a huge shock in political circles, and will put pressure on the Coalition and lead to calls for a general election.
A general election must be held by March 2025, and rumoured times for when the Government will call one have ranged from this summer to November.
Whether this will change now, remains to be seen.
In the speech announcing his decision to stand down, Mr Varadkar indicated his successor would have a year to work with, while Tánaiste Micheál Martin also insisted the Coalition will continue.
However, Wednesday's shock news will certainly make the Government more unsteady.
With this in mind, contenders to succeed Mr Varadkar may prefer to bide their time before bidding to be the next party leader, rather than being seen as a lame duck taoiseach.
This point is uncertain at the moment, but here we look at the figures who have a chance at taking over from Mr Varadkar.
Simon Harris
Minister for Higher Education Simon Harris will undoubtedly be considered the favourite.
Mr Harris has made no secret of his leadership ambitions in the past, and recently served as Minister for Justice along with his education post during Helen McEntee's maternity leave.
He is a popular figure in the party, and at 37, would have plenty of time to lead in a likely period in opposition after the next general election.
In an interview with BreakingNews.ie in January, former Fine Gael government minister Ivan Yates said there is "no betting" on Mr Harris being the next party leader.
Mr Yates said: "I think that there is no betting that Simon Harris will be the next leader of Fine Gael. I think he would rather take on the party in opposition with Sinn Féin in government. He would see it as fertile ground for the party to grow its identity, its brand and its base in the middle class, self-employed, and business communities, to get a solid party of 40 to 50 seats going forward.
"I think he toyed with the idea of taking on Leo before and thought the better of it. Let's be clear, Leo is no longer the future. I don't say that out of any dislike or disrespect for him. Everybody reaches a point in their political career where they were once the future and are no longer the future and Leo has reached that point."
He added: "In terms of a competitor to Harris, who wants it and has the best CV, connections and network inside and outside the party, Helen McEntee has gone backwards with her term in justice. I think she's a nice person but lacks authority and that's not what's required in a minister for justice or party leader.
"I think Jennifer Carroll MacNeill will be the likely opponent for Simon Harris."
Simon Coveney
Minister for Enterprise, Trade and Employment Simon Coveney is now one of the most senior figures in the party.
He ran against Mr Varadkar for the leadership in 2017. Another bid is very possible, but party members may prefer a fresher candidate.
At 51, Mr Coveney is still young in political terms, but he was elected as a TD in 1998, and rumours have suggested he has been planning for life post-politics.
This is evident in the fact that rumours initially suggested it was Mr Coveney announcing he would step down, before it became apparent the news was about Mr Varadkar.
Helen McEntee
Helen McEntee was once seen as the most likely rival for Mr Harris to be the next Fine Gael leader.
However, her spell as Minister for Justice has not gone as well as she would have hoped.
Issues like Garda body cams, planned hate speech legislation, and a number of high-profile violent attacks in inner-city Dublin have impacted her approval ratings, while Sinn Féin's motion of no confidence in Ms McEntee after last year's Dublin riots pointed to level of discontent in the Minister's handling of the justice portfolio despite being voted down in the Dáil.
Paschal Donohoe
Minister for Public Expenditure Paschal Donohoe is seen as one of the most competent, hard-working and efficient politicians in the Coalition by those in his party and others.
If the former minister for finance decides to run for the party leadership, he would be a favourite to succeed Mr Varadkar.
However, he has indicated on a number of occasions he has plans beyond politics.
He is the leader of the Eurogroup of finance ministers, and has also been linked with roles in the European Commission in the recent past.
Jennifer Carroll MacNeill
Jennifer Carroll MacNeill, Minister of State at the Department of Finance, is an ambitious TD and is highly thought of by her Fine Gael colleagues.
She would be an unlikely candidate, but could decide now is the right time to bid for promotion.
Ms Carroll MacNeill was elected as a TD in 2020.
