A FORMER Labour First Minister has called on his party to develop a radical devolution blueprint and propose putting it to Scots, potentially alongside the option of full independence, in a new referendum.

Henry McLeish warned that his party had been "running away" from a debate on Scotland's future for at least a decade, and that if did not come up with the "passion and confidence" to offer bold new ideas that would win the backing of the public, Labour would have "no future".

The ex-Scottish Labour leader, who led the country between 2000 and 2001, backed growing calls for Kezia Dugdale to confront the issue of the constitution following the party's disastrous showing at the Holyrood election and embrace a radical new approach of home rule within the UK, before putting faith in the people to shape the country's future.

READ MORE: Inside the Scottish Labour campaign: no focus, no money, no hope

He said that many Scots were yet to be fully convinced by either full independence or the status quo, and that a strong, federalist alternative would allow a reinvigorated Labour to be the architects of a sustainable middle ground. However, he said an ongoing drip-feed of powers from a reluctant Westminster to Holyrood would make independence inevitable.

The dramatic intervention from the party grandee comes after Alex Rowley, Ms Dugdale's deputy, blamed Labour's collapse on its failure to embrace genuine home rule and Anas Sarwar, one of the party's new MSPs, admitted the once dominant political force in Scotland were not comfortable as unionists or nationalists.

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Mr McLeish said that the party should embrace civic society in coming up with its new constitutional settlement and then head into the next Holyrood election offering Scots the chance to support it in a referendum, and that a third option of independence could also be included alongside the status quo.

He said: "We have got to accept that just saying no to independence is not a strategy or solution. If we accept that, we can go on to develop a credible path forward for Labour that gives the public the debate they want. There should come a time when Labour has the courage and confidence to take the Tories and SNP on over the constitution. We should be offering up a referendum on a new alternative of real home rule.

"People might say that’s a bold option, and yes it is. But I can’t see an alternative way forward and if we’re serious about Scotland’s future, people deserve choices. We are not going back to the old days, and I like the idea of the absolute sovereignty of the Scottish people. We have got to trust them to shape their destiny.

"I believe Scots have not yet decided on the future because they are not fully attracted by either of the two options - grudging concessions from Westminster or straight independence. I believe Labour's future lies in unlocking a door to a more viable path, ridding the country of this narrow debate. Scots have not been given a viable, sustainable, attractive alternative to independence.

"Be in no doubt, unless we can get an audience on Scotland’s constitutional future, and take people with us, for Labour there is no future."

READ MORE: Inside the Scottish Labour campaign: no focus, no money, no hope

Mr McLeish accepted that his proposals would likely be strongly opposed by UK party power brokers in London, who once relied on Scottish voters returning a significant bloc of Labour MPs, but said Jeremy Corbyn should be "confronted" and told there is now no option other than the Scottish party becoming autonomous within a federal UK.

He attacked the current constitutional settlement, saying the further powers destined for Holyrood had been dragged out of the UK parliament, with a cynical 'vow' of further devolution only being made as a result of a feeling of crisis in London as it sunk in that Scotland could back independence in 2014.

He added: "Many in Labour still feel that to embrace nationality and identity requires us to undermine or history and our socialism. Nothing could be further from the truth. Throughout the world right now, nationality and identity are legitimate issues being discussed.

"It's not selling out, it's not aping the nationalists. We now have an opportunity to develop a substantial solution that would have Labour's brand on it. This can't wait because of local government elections or anything else, this is about the very future of our party and our country.

"When the party is down, it is often very difficult to raise our heads and look at future horizon. But we need to think boldly and wisely and go into areas that we have not gone before.

"Kezia Dugdale had a good campaign in some serious ways. She is dignified, principled, wanted to stick with her policies and showed a good sense of humour. Labour voters were hearing this but it hadn't got through the constitutional barrier. She has got to have early discussions with London, get much better advice from her inner circle, put behind notions of yesterday's politics and grasp the new reality.

"The party apparatus can close down debate too often. Within three to four months she should be opening up a big debate, which has at its heart an answer to the constitutional question and giving people the chance to reconnect and reengage."