RULING out support for indyref2 has left Scottish Labour “looking intransigent, undemocratic, and tone-deaf,” a close ally of Jeremy Corbyn has claimed.

The comments, made in an article for the Tribune by Glasgow councillor Matt Kerr, are the latest salvo in the party’s increasingly bitter civil war over the constitution.

The left-winger – who recently lost out to Jackie Baillie to be Labour’s deputy leader – says the party will not even be able to reclaim second place at the next election unless it can win back Yes voters.

Kerr said the victory for the No campaign in 2014 “was the very definition of pyrrhic”.

He added: “The independence movement had grown massively during the campaign, and built an enthusiastic base. ‘Better Together’, meanwhile, had looked like a defence of the status quo – and even as it mounted a successful rearguard action on the Union it damned the Labour Party as a force for change or progress in the eyes of working-class Scotland.

“The Labour Party’s involvement in it was seen by huge swathes of our support as being in bed with the Tories, who were busily destroying lives in our communities. People were angry, but not just anyone – people who had been lifelong Labour voters, supporters, and even members were angry.

“And yet, the machine rolled on. What came next was a catastrophic defeat in 2015 after a campaign that will be remembered for canvassers being literally chased out of streets where the Labour vote a few years earlier would have been weighed, not counted. “

Earlier this month, Scottish Labour’s ruling executive committee voted to oppose indyref2 in its Holyrood election campaign next year.

Speaking at the time, Richard Leonard, the Scottish Labour leader, said: “We agreed to campaign for a programme of home rule, devolution and democratic advance within the UK.”

Ian Murray, the shadow Scottish secretary, and Baillie, the party’s deputy leader in Scotland, have both been vocal opponents of a second vote.

Others, including health spokesperson Monica Lennon and veteran MSP Neil Findlay, have previously said the party should not stand in the way of a new referendum.

In the article, Councillor Kerr, who makes clear he would vote and campaign for No in any future indyref2, said Labour’s decision ensures next year’s Holyrood election will be dominated by the constitution.

He added: “There are many ex-Labour voters out there who voted Yes, the majority of whom have not returned to the party. Some may be diehard supporters of independence now, but many aren’t.

“They departed from the Labour Party because they saw us as representing a status quo that wasn’t working and they still see us that way. We have failed – not to convince them about our view on independence, but to convince them that our policies would improve their lives more than the SNP.”

He added: “The Labour Party in Scotland has no route back to second place, never mind power, unless it is willing to reach out to those people. No-one aspiring for real change can be satisfied with the SNP. But the reality is, they couldn’t be convinced by the Labour Party either.

“Ruling out another referendum in all circumstances leaves us looking intransigent, undemocratic, and tone-deaf.”

Kerr was the party’s candidate in Glasgow South West at last December’s General Election. On the final day of campaigning, Jeremy Corbyn was in the constituency to kick off his tour of the UK.

It was a key Labour target, but the SNP increased their majority from just 60 votes to 4900.