NICOLA Sturgeon has written and signed her resignation letter to King Charles.

The outgoing FM - who has been in post for 3051 days - has formally tendered her resignation after Humza Yousaf won the SNP leadership contest.

He is set to become first minister today if the Scottish Parliament gets behind him.

Sturgeon tweeted: "Just signed my formal letter of resignation and departed Bute House for the final time.

"Next stop @ScotParl to vote proudly for @HumzaYousaf as Scotland's sixth first minister.

"From me - for now - thank you Scotland for the privilege."

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It is a requirement under Section 45 of the Scotland Act 1998 for the outgoing FM to formally tender their resignation to the monarch. The new first minister will be appointed by the King on the recommendation of the Scottish Parliament.

At around 11.20 on Tuesday it was reported the King had accepted Sturgeon's resignation.

As she walked down the famed stairs of Bute House, adorned with pictures of the first ministers who occupied the building previously, a nail could be seen protruding from the wall, ready for the picture of her successor.

In her letter, Sturgeon wrote: "With my humble duty, I write as anticipated in my letter to Your Majesty of 15 February to tender to Your Majesty my resignation from the office of First Minister.

"I propose that my resignation take effect from the start of the Scottish parliamentary plenary business on Tuesday 28 March 2023.

"I should wish to reiterate that it has been my pleasure to serve Your Majesty, Her Majesty the Queen and the people of Scotland as First Minister since November 2014.

"I have the honour to be, Sir, Your Majesty's humble and obedient servant."

She added in a further comment: “Being first minister of the country I love has been the privilege of a lifetime – an opportunity for which I will always be grateful beyond words to the people of Scotland.

"As the first woman to hold this office, I am proud to demit it knowing that no girl in our country is in any doubt that a woman can hold the highest office in the land.

"My congratulations go to Humza Yousaf who, subject to Parliamentary process and appointment by His Majesty the King, will become the first person from a minority ethnic background to lead our country as its first minister – and in doing so will reiterate the powerful message that it is a role that any young person in Scotland can aspire to.

The National: Nicola Sturgeon gave hugs to her staff as she left Bute House for the last timeNicola Sturgeon gave hugs to her staff as she left Bute House for the last time (Image: PA)

“Every day in this office is an opportunity to make something better for someone, somewhere in Scotland.

"That has been my guiding mission throughout my time in office, and the motivation behind everything my government has stood for.

"I think it is evidenced in much of what we have achieved: doubling of early years education and childcare; the Scottish Child Payment; widening access to higher education with a record number of young people from backgrounds like mine now going to university; minimum unit pricing, a policy that is saving lives; a publicly-owned, mission driven national investment bank; and putting the climate emergency at the heart of all we do.

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“That’s not to say that every day was straightforward – all of the achievements I am proudest of involved taking steps that were difficult but vital. This was also the case in by far the toughest challenge of my time as first minister – leading Scotland through the pandemic.

“Covid shaped all of us - I know that it changed me, and, in many ways, it defined my time as First Minister. But the pandemic showed us how much we can achieve when we face huge challenges with common purpose.

"Above all, it reinforced in me an abiding admiration for the people of this wonderful country, who made such painful sacrifices to keep each other safe. In the toughest of times, our country showed the best of itself with love, care and solidarity. That will live with me for ever.”