Scottish Labour yesterday kick-started talks on a second independence referendum by staging an emergency meeting of party elders.

The move, in the wake of Scotland voting overwhelmingly to remain in the EU, comes after one major union signalled it may soften its opposition to independence.

Leader Kezia Dugdale said she is mulling over “all options” amid the prospect of Scotland being taken out of the EU.

The UK voted for Brexit on Thursday, but voters north of the border  supported the Remain option.

First Minister Nicola Sturgeon, who played down talk of another independent referendum during the Holyrood election campaign, says a second poll is “highly likely”.

If Sturgeon pursues this option, she is certain to win support from a majority of MSPs.

The Scottish Tories, under the revitalised leadership of Ruth Davidson, would be expected to lead the opposition to the plans.

However, the likelihood of a snap independence poll now puts Scottish Labour under pressure.

In its latest Holyrood manifesto, Dugdale stated: “We rule out another referendum on independence during the lifetime of the next Parliament.”

However a senior party source said the commitment was made in a pre-Brexit era.

Another source said Labour could not ignore the parliamentary arithmetic at Holyrood and could be punished for standing in the way of another referendum.

Against this backdrop, Scottish Labour convened a summit of MSPs, council group leaders and Executive members in Glasgow.

The purpose was to seek views on Labour’s response to Brexit and how to deal with the question of a second independence referendum.

Dugdale said yesterday: “We believe in the redistribution of wealth and power, and we believe that by the strength of our common endeavour we achieve more than we ever could alone.

She added: "As a party, we will now go forward driven by those enduring values and apply them to our duty to do the best thing for Scotland and interests of working people within it.

"On that basis, we will consider all options and do so in a democratic fashion in keeping with our party's finest traditions.

“It is clear that, rather than being the party who stands up for the United Kingdom, all the Conservatives have done since the 2014 Scottish Independence referendum is put the United Kingdom in danger."

At the beginning of the Holyrood election campaign, Dugdale speculated that she could “possibly” back independence if it meant Scotland staying the EU.

She was criticised for the comments and eventually put a commitment to opposing a second referendum in the manifesto.

However, the hypothetical situation she commented on – the UK voting to leave the EU - has now come to pass.

Meanwhile, the Scotland Secretary of the GMB union has said his organisation is to hold discussions with its members on the “constitutional question”.

Gary Smith told the Sunday Herald yesterday: “GMB took a position that was No in 2014.

"But with the prospect of a right-wing government down south, burning through workers’ rights, it is simply not credible to say we would be against independence in all circumstances.

"I don’t think our members would accept that.”

He added that the First Minister still had “tough questions” to answer about independence.

Former Labour Minister Tom Harris criticised Dugdale's statement: “Labour supporters who back the UK will wonder what the Labour party is actually for.

“The statement is the kind of innocuous, meaningless nonsense that gives politics a bad name.

"If they are going to be ambiguous on the UK and ignore the democratic result on the EU, then they can’t call themselves democrats.”

A Scottish Tory source said: "Ruth is very clear that a second referendum on independence should be resisted in the strongest possible terms.

"But by the sounds of this, Labour are once again wavering on the union, and don't appear to be too concerned about the prospect of the SNP using last week's vote as an excuse to agitate for separation."