LABOUR leader Sir Keir Starmer is likely to back a multi-option second independence referendum with "devo max" on the ballot paper, according to a former top aide to the Scottish Conservatives.

Andy Maciver, a former communications director for the Scottish Tories, said he could not envisage Boris Johnson agreeing to such a vote.

He added that he believed it was the position Labour were heading towards but warned it would be damaging to the independence campaign.

"The whole issue is defining what devo max is," he told The National adding that it could be regarded generally as the middle option alongside the status quo or independence.

He said polling had previously shown it was very popular.

"My own view is that it would be a better option for unionists than nationalists. I think if the Union is going to survive that is the only way it is going to survive. I think it would give the vast majority of people what they want," he said.

"I think it would be very damaging to the independence campaign. With devo max as an option, I don't think there would be enough support for full independence."

Maciver added: "You are looking potentially at that being the Keir Starmer option. It wouldn't have to be put to a referendum.  He could stand on a manifesto of Home Rule for Scotland and other parts of the UK."

Earlier, lEADING Unionist commentators suggested a multi-option referendum would be a trap for supporters of the UK.

Stephen Daisley, a columnist for the Spectator and Daily Mail, cited The National's front page today which reported on senior SNP activist Chris Hanlon backing a three-way vote with devo-max as an option in a second independence referendum.

"This couldn't be more of a trap if it had been painted on the side of a mountain by Wile E. Coyote," wrote the journalist on Twitter this morning as he attacked Hanlon's suggestion.

READ MORE: Indyref2: Ex SNP policy chief backs three-option ballot paper to break 'logjam'

Henry Hill, news editor of the Conservative Home website, said it was a plan that "might come about" describing it as "the next iteration of "the best of both worlds".

The National:

Political commentator Stephen Daisley

"Basically as many of the advantages of the Union as they can get away with, with as few obligations as possible. Wholly unsustainable and iniquitous, as the separatists know," he tweeted.

One UK supporter wrote that the three-way referendum was "never going to happen, not least because the electorate can’t even comprehend what indy might look like".

"Never mind another option equally lacking in sufficient detail that all parties can put their own interpretation of what that might be."

READ MORE: Indyref2: Why devo-max should be an option at the next referendum

But Hill responded: "That lack of detail is precisely how it might come about. It's just the next iteration of "the best of both worlds".

Hanlon, who sits on the SNP's policy development committee and is the party's former policy convener, suggested that the option may help to break a constitutional "logjam". He underlined he would vote for independence.

Since the EU referendum in 2016, the SNP has been demanding a second independence referendum with the UK Government repeatedly refusing to agree to a new vote.

First Minister Nicola Sturgeon told the SNP conference in November that independence campaigning would begin "in earnest" this Spring.

The Scottish Government have pledged to hold a second independence referendum before 2023, so long as the pandemic is over.

However, Prime Minister Boris Johnson has repeatedly refused to agree to a new vote.

His refusal has prompted the SNP to pledge to hold a new vote using Holyrood's powers should he continue to block an agreed referendum.

The UK Government may then take the Scottish Government to the Supreme Court to challenge the legality of a Holyrood-run indyref2.

Responding to Hanlon's proposal, Scottish Lib Dem leader Alex Cole-Hamilton rejected any form of referendum.

"The last thing Scotland needs is any kind of referendum right now," he said.

"I am baffled that anyone can look at the state of the NHS, Scottish education and the economy and conclude that what we need right now is to spend years arguing about independence.

"There is plenty for the Scottish Government to be getting on with just with the pandemic."