DUP Leader Peter Robinson has resigned as First Minister of Northern Ireland.
The move comes after a warning he would quit earlier this week.
It's been a tumultuous few weeks for the power-sharing government in the North, stirred by police claims that the IRA are still in operation.
Robinson was elected to the Northern Ireland Assembly in 1998 representing East Belfast and again in 2003, 2007 and 2011.
He became First Minister of Northern Ireland in June 2008.
In a statement, Robinson said he was quitting with immediate effect and that all other DUP Ministers would do the same with the exception of one.
Arlene Foster, a "strong advocate for Unionism" from South East Fermanagh will step in to act as First Minister to ensure "that nationalists and republicans are not able to take financial and other decisions that may be detrimental to Northern Ireland."
Read Peter Robinson's statement in full here:
As someone who invested many hours trying to bring devolution to Northern Ireland, and to maintain it, I have tried to create space to allow these critical unresolved matters to be dealt with in a structured manner.
Local Ministers making local decisions is best for Northern Ireland.
The failure of the SDLP and Sinn Fein to implement the Stormont House Agreement together with the assessment from the Chief Constable of the involvement of IRA members in murder, the continued existence of the IRA and the arrests that followed has pushed devolution to the brink.
Yesterday I indicated that we would ask the Business Committee to adjourn Assembly proceedings to allow negotiations to take place. That proposal did not find sufficient support. The Government can still legislate to suspend the Assembly and allow space for the parties to negotiate.
In light of the decision by republicans, nationalists and the UUP to continue with business as usual in the Assembly, I am therefore standing aside as First Minister and other DUP Ministers will resign with immediate effect with the exception of Arlene Foster. I have asked Arlene to remain in post as Finance Minister and acting First Minister to ensure that nationalists and republicans are not able to take financial and other decisions that may be detrimental to Northern Ireland.