Deputy First Minister John Swinney has ruled himself out of the SNP’s leadership race, disappointing those who thought he was best placed to unite the party.

The party’s governing body has set a deadline of 24 February for nominations and Kate Forbes as well as the favourite the job Angus Robertson are likely to put their names forward. Humza Yousaf and Ash Regan are other potential candidates.

A special conference scheduled for next month on Nicola Sturgeon’s plan to treat the next general election as a de facto independence referendum has been postponed.

The party’s NEC said that it was delaying the conference until there is a new leader who will be announced on 27 March.

Westminster leader Stephen Flynn had earlier called for a postponement of the conference in the light of the resignation of Nicola Sturgeon. She had proposed the de facto vote but it has divided opinion in the party.

SNP National Secretary Lorna Finn said:  “I am pleased to confirm that SNP NEC has tonight agreed a timetable for party members to select a new leader of our party and country. 

“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. 

“Should there be a contest, with two or more applicants, then the selection of the new leader will be held on a democratic one-member-one-vote basis.

“Democracy is in crisis in the UK right now, but the SNP and Scotland’s future must and will be decided by the ballot box. 

“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.”