image copyrightPA Mediaimage captionEdwin Poots left the meeting shortly after 20:00 BST on Thursday
Edwin Poots has resigned as leader of the DUP after just 21 days.
His resignation came after a meeting of party officers in Belfast where he faced an internal revolt.
That revolt began after Mr Poots agreed a deal with the secretary of state, Brandon Lewis, on Irish language legislation.
Mr Poots took over from Arlene Foster in May. He narrowly defeated Sir Jeffrey Donaldson in a leadership election.
Earlier on Thursday, Paul Givan was nominated as the new first minister for Northern Ireland, despite protests from DUP colleagues who wished to delay the process.
The BBC understands a motion of no confidence was mentioned but not tabled at the meeting of DUP officers.
Party sources described the meeting as "robust" and said it had become clear Mr Poots knew he had to resign.
It is thought the process to appoint his successor could move "at pace", according to one DUP figure.
For 21 days, Edwin Poots was living the dream, leading the party his father helped found, the party he joined as a teenager.
His DNA was DUP, but nobody could have predicted how quickly the dream turned sour.
He grabbed power by insisting he would be a "listening leader" for his fellow MLAs who had felt their voices weren't heard during the Foster years.
But ironically, his downfall was sealed when those same MLAs were ignored by their new leader.
They demanded that Edwin Poots stall the nomination of Paul Givan as first minister, but he didn't listen.
His fate was sealed and his dream was short lived.
In a statement, Mr Poots said he had asked the party chairman Lord Morrow "to commence an electoral process within the party to allow for a new leader of the DUP to be elected".
He said it had been "a difficult period for the party and the country".
"The party has asked me to remain in post until my successor is elected. I have conveyed to the chairman my determination to do everything I can to ensure both unionism and Northern Ireland is able to move forward to a stronger place."
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Responding to the news, a Sinn Féin spokesperson said the DUP leadership was "a matter for that party".
image captionMr Poots leaves Thursday's meeting, surrounded by media
In a statement they added: "Sinn Féin has worked for weeks to bring stability to the executive.
"We have monumental challenges ahead that will require unity of purpose and urgency. They include tackling the totally unacceptable hospital waiting lists that have left people crucified, in pain and without hope.
"That is our focus and should remain the focus of all ministers in the executive."
The nationalist Social Democratic and Labour Party (SDLP) leader Colum Eastwood tweeted that he was "sick of this soap opera".
"We're in the middle of a pandemic, waiting lists are sky rocketing, our economy is in crisis. Maybe it's time for some grown up politics."
A DUP source tells me: “The party needs stability and Jeffrey (Donaldson) is stability. The party needs to stop this nonsense and coalesce.”
— Jayne McCormack (@BBCJayneMcC) June 17, 2021
The BBC is not responsible for the content of external sites.View original tweet on Twitter
Ulster Unionist Party (UUP) leader, Doug Beattie said the situation was "inevitable".
"It doesn`t matter who the leader of the DUP is because they will face the same critical issues which were negotiated and agreed on their watch," he added.
Stormont sources have said say the planned North South Ministerial Council meeting will now not be going ahead on Friday.
image copyrightPAcemakerimage captionPaul Givan and Michelle O'Neill were confirmed as first and deputy first ministers during a special meeting of the assembly on Thursday
Mr Poots had named Mr Givan as the party's choice to replace Mrs Foster as first minister, while Sinn Féin said Ms O'Neill would resume her post as deputy first minister.
The vast majority of DUP assembly members (MLAs) – 24 to four – voted against Mr Poots nominating Mr Givan as first minister, during a meeting ahead of the special assembly sitting.
Sinn Féin had wanted commitments from the DUP over a timetable for implementing Irish language legislation, as set out in the New Decade, New Approach deal (NDNA) that restored power sharing in January 2020.
The party called on Brandon Lewis to bring in Irish language legislation via Westminster.
Mr Poots had said he was committed to implementing all of the NDNA commitments, including those around Irish language, but not necessarily before the end of the current assembly mandate in May 2022.
When a deal was reached in the early hours of Thursday, Mr Lewis said he was "disappointed" the Stormont executive had not brought Irish language legislation forward in the assembly.