Nicola Sturgeon will stand down as First Minister after eight years because she believes resigning is the best move for herself, her party and for Scotland.
In a shock announcement, the SNP leader told a press conference on Wednesday she believed it was the right time to stand aside.
She denied she was reacting to "short-term pressures" after a series of political setbacks.
The longest serving - and first female - First Minister said from her residence at Bute House in Edinburgh that she would remain in office while the SNP select her successor.
"Since my very first moments in the job I have believed a part of serving well would be to know almost instinctively when the time is right to make way for someone else," she said.
"In my head and in my heart I know that time is now. That it's right for me, for my party and my country."
Ms Sturgeon, who guided the nation through the coronavirus pandemic and led the SNP to repeated election victories at UK, Scottish and local level, acknowledged the "physical and mental impact" of the role.
"If the question is can I battle on for another few months then the answer is yes, of course I can," the 52-year-old said.
"But if the question is can I give this job everything it demands and deserves for another year, let alone for the remainder of this parliamentary term, give it every ounce of energy that it needs in the way that I have strived to do every day for the last eight years, the answer honestly is different."
Ms Sturgeon has suffered a series of political setbacks in recent months as her government sought to push through gender reforms, only for them to be blocked by Westminster.
Ms Sturgeon acknowledged the "choppy waters" but insisted her resignation was not in response to the "latest period of pressure".
Ms Sturgeon rose to power unopposed after the ill-fated independence referendum in 2014, taking over from Alex Salmond, the mentor with whom she would come into conflict in the years to come over the handling of sexual harassment allegations made against him.
Her surprise exit led political commentators to draw parallels with the sudden resignation last month of Jacinda Ardern as New Zealand's prime minister.
Ms Sturgeon vowed to continue in politics and said her life-long cause of independence is "being won".
Ms Sturgeon indicated she will continue on the backbenches as an MSP "until, certainly, the next election" for Holyrood, which is due in 2026.
Australian Associated Press
