Deputy First Minister John Swinney has said he will not be standing to take over Nicola Sturgeon as leader of the SNP.
His announcement comes as the SNP announced it has postponed its special conference, with the party saying the ballot to select the First Minister’s successor will close on March 27.
The party’s new leader is to be revealed as soon as the ballot has been determined.
Swinney, who has been in the Scottish Parliament since 1999 and served as leader of the party between 2000 and 2004, said he had “thought carefully about whether I should stand and have had to be sure whatever I do is right for my family, the Scottish National Party and our country”.
He added: “For the best part of the last 40 years, I have had the privilege of being at the very heart of formulating the strategy of the SNP. From a very poor starting point in the 1980s, I am proud to have played my part in building the SNP into a successful party of government in Scotland with an impressive electoral record.
“The refusal however of the UK Government to respect the democratic wishes of the people of Scotland to have a referendum on independence, requires the SNP to consider carefully, and in my view with a fresh perspective, how to pursue our aims. To create space for that fresh perspective to emerge, I have decided not to be a candidate for leadership in the SNP.
“At this critical moment, I believe there must be an open debate within the SNP about our direction. I encourage those who stand for election to bring forward perspectives which anchor the SNP in the mainstream of Scottish politics which is an absolutely critical requirement for the future success of our cause.
“For my part, I will continue to do what I have done since I was 15, and that is to contribute constructively to advance the interests of the SNP, Scotland and the cause of Scottish independence.”
Nominations for the post are open after a meeting of the party’s national executive committee and those eying the top job have until February 24 to submit their nomination, with the vote open between March 13 and 27.
Lorna Finn, the party’s national secretary, said: “Nicola has been the outstanding politician of this generation.
“We are very fortunate that she will remain an SNP MSP and a leading campaigner for an independent Scotland.
“But the SNP is full of talented individuals and they now have the opportunity to put themselves forward and our new leader will lead us into the final phase of Scotland’s journey towards independence.”
The results of the contest will be made public as soon as the result is determined, the party said, and after the candidates have been told.
Its planned meeting on March 19, in which members were set to discuss the path towards an independence vote.
Sturgeon had backed the use of the next general election as a de facto referendum.
But the party on Thursday said that would be postponed.
Ms Finn said: “It would be wrong to have a newly elected leader tied to a key decision on how we deliver democracy in Scotland in the face of continued Westminster intransigence.
“Therefore, the party’s special democracy conference, previously planned for Sunday March 19, is postponed.
“SNP Members, the lifeblood of this party and movement, will be updated in due course on details of a rearranged event once the new party leader is in place.