SCOTTISH Labour is set for a major battle between its left and centrist wings over who can vote in its leadership contest, as the party faces fundamental questions over its future direction.

Jeremy Corbyn supporters want to set a deadline for new members being allowed to vote after the campaign has officially begun believing new and younger members will back a candidate sympathetic to the UK leader.

However, figures in the centre want an early cut-off point to stop the Corbynistas taking over the party’s grassroots as they have south of the Border.

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The row promises to mirror ones which dominated the UK Labour leadership contest in 2015 when rival camps furiously signed up members and registered supporters they thought would back their candidate.

The issue prompted Labour chiefs to embark on expelling members they suspected of joining to undermine the party but many were angry they were wrongly “purged”.

A Labour source said he expected the forthcoming Scottish Executive Committee meeting tomorrow week to be dominated by the issue of who can vote and when the deadline for members to sign up will be.

Pat Rafferty, Scottish secretary of the trades union Unite, which backs Corbyn’s leadership, called for a delay in the leadership contest earlier in the week.

His intervention was interpreted as giving more time for candidates to come forward, but yesterday a Labour insider said the key issue behind the move was delaying the cut-off for allowing new members to vote.

“This issue of the delay in starting the campaign has been presented as being about giving more time for candidates to come forward. But I’m not convinced of that as I think it will be clear over the next couple of days who the candidates will be,” he said.

“The logical argument for delaying is to agree a freeze date for members, setting a date at which if you are not a member by that date you don’t get a vote. That’s always a difficult issue.

“The case for delaying is to use a future freeze date and leadership election as a means to encourage people to join the party and participate in the leadership election.”

The source set out the scenario after James Kelly, the Glasgow MSP and Scottish Labour’s business manager, who is on the centre of the party, said his preference was for a freeze date before the official campaign began.

In an interview with BBC Radio Scotland’s Good Morning Scotland, he said: “I don’t favour the process we had in 2015 when people could join the party during the course of the actual leadership election. I don’t think that’s the way to go forward.

“There has to be an adequate cut-off point which recognises we’ve had a surge in membership over recent months.”

On Wednesday, Rafferty called for the party to reflect and “not to act in undue haste on any succession plan”.

He said: “Under Alex Rowley’s interim leadership we are confident that the voices of Scotland’s working people will be heard loud and clear at Holyrood. This is not about the next four weeks. It is about the next four years. This is an opportunity to reflect upon what the Scottish Labour Party stands for. Let’s seize it and build for the future.”

Dugdale stunned party members in Scotland when she announced on Tuesday night she was stepping down from the job with immediate effect. The surprise move came after a five-day visit to Scotland last week by Corbyn.

Dugdale had been leader of Scottish Labour for two years, taking over from Jim Murphy after the disastrous 2015 General Election campaign saw the party lose 40 of the 41 seats it held north of the Border.

The two most likely candidates to take over from her are Holyrood health spokesman Anas Sarwar, who has previously been an MP and deputy leader of the Scottish party, and Richard Leonard, a former GMB trade union organiser who was elected to the Scottish Parliament in 2016.

But despite Scottish Labour having had had three leaders quit since the 2014 independence referendum, he dismissed any suggestion the position was a poisoned chalice.

He claimed Labour north of the Border had enjoyed a “surge in membership” in recent months, but could not give any details of how many new recruits had joined.

He described both Sarwar and Leonard as “excellent parliamentarians”.

Labour’s Scottish Executive Committee meet on Saturday, September 9 to agree the timetable and process for a leadership election.