She said: "A short time ago I called the Party Chairman to inform him that I intend to step down as leader of the Democratic Unionist Party on the twenty-eighth of May and as First Minister of Northern Ireland at the end of June.
"It is important to give space over the next few weeks for the Party Officers to make arrangements for the election of a new leader. When elected I will work with the new leader on transition arrangements.
"As First Minister it is important that I complete work on a number of important issues for Northern Ireland alongside other Executive colleagues. Northern Ireland and its people have been heavily impacted by the Covid-19 pandemic and there remains more work to be done to steer us thorough the pandemic and to lessen its impact on the lives of everyone.
"It has been the privilege of my life to serve the people of Northern Ireland as their First Minister and to represent my home constituency of Fermanagh/South Tyrone. I first entered the Assembly in 2003 and undoubtedly the journey of the last eighteen years has been memorable. There are many people who have helped and supported me throughout that period and I will always been grateful for the kindness and support shown to me by them."