Scotland’s first minister Nicola Sturgeon has announced her resignation, saying the job “takes its toll on you and all around you”.
The SNP leader made the the shock announcement during a press conference in Edinburgh at her official residence, Bute House.
She said it had been “the very best job in the world” and one that has “sustained and inspired me in good times and in the toughest hours of my toughest days”.
But Ms Sturgeon said she believed part of “serving well would be to know almost instinctively when the time is right” to step down, adding: “In my head and in my heart I know that time is now, that it is right for me and my party and for the country.”
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The longest serving and first woman first minister insisted her decision was not down to “short term pressures”, such as the ongoing divisions in her party about transgender rights, but something she had been considering over weeks.
She said instead her exit “frees the SNP to choose the path it believes to be the right one” when it comes to campaigning for Scottish independence “without worrying about the perceived implications for my leadership” ahead of a special conference next month.
And Ms Sturgeon said was a personal decision too, saying: “I am not expecting violins here, but I am a human being as well as a politician.
“Giving absolutely everything of yourself to this job is the only way to do it. The country deserves nothing less.
“But in truth that can only be done by anyone for so long. For me, it is now in danger of becoming too long.
She added: “To those who do feel shocked or disappointed, or perhaps even a bit angry with me, please… be in no doubt that this is really hard for me.
“My decision comes from a place of duty and of love. Tough love, perhaps, but love nevertheless for my party and above all for the country.”
The first minister confirmed she would stay in post until somebody else takes over and remain as an MSP until at least the next Holyrood election.
She said the SNP would announce the process for electing a new leader over the coming days, but refused to say who her preferred candidate would be.
Members of her party have begun paying tribute to her time in office, with SNP president Michael Russell thanking her for her “extraordinary and brilliant leadership of her party and country”.
SNP MP Alison Thewliss said she was “absolutely gutted” about the news, adding: “Nicola has been an incredible leader.”
Fellow MP Stewart McDonald, called Ms Sturgeon “the finest public servant of the devolution age” and said it would be “an enormous loss” to the country and party.
And another SNP MP, Kirsten Oswald, described her as “outstanding”, adding: “We’ve been so fortunate to have someone with her talents at the helm. I am so sorry she is standing down.”
Ms Sturgeon has led the party and the country since 2014 after taking over from her predecessor, Alex Salmond, making her the longest serving first minister since devolution to Holyrood.
But she has been involved in the SNP all her adult life, joining the party at the age of 16.
As first minister, she has secured election successes at every poll and continued to push for Scottish independence, campaigning for a second referendum on the decision.
That, along with her strong anti-Brexit stance, has left her at loggerheads with the UK government, led by the Conservatives, who back keeping the UK together and have refused to offer up another vote on independence.
A senior Labour source said her decision showed it was “all over” for the independence campaign, and showed “after 15 years of failure, the SNP have run out of road”.
There have been a number of tricky issues for Ms Sturgeon in recent months, including splits in the party over her approach to transgender rights, and over her bill on gender recognition.
Despite passing the legislation in Holyrood – which would have meant people could legally change their gender in Scotland without a medical diagnosis of gender dysphoria – the bill was then blocked by Westminster, with ministers claiming it would have a “significant impact” on equalities.
Sky News political correspondent Tamara Cohen said Ms Sturgeon’s popularity “had taken an unusual knock in recent months in polls, for the first time since she became first minister” but the news still came as a surprise.
There has also been change at the top of the SNP in Westminster in recent months, with Sturgeon ally Ian Blackford being replaced as leader in December by Stephen Flynn.