The campaign for an alternative to independence has gathered pace, with a new report laying the groundwork for Unionist parties to adopt before the next general election.
The Devo Plus movement hopes to persuade anti-independence parties to use its blueprint for more tax powers and responsibility at the Scottish Parliament, in the event of a No vote in the 2014 referendum.
Group leader Jeremy Purvis, a former Liberal Democrat MSP, said agreement is possible and desirable.
"As part of discussions with party leaders, we have been presenting the case to them that they can have confidence that there is a lot of work being done, that there is a worked-up set of proposals that are deliverable," he said.
"As the party leaders go through their own party procedures, I would like to think we have presented the strongest case where they can coalesce around."
He continued: "I most certainly think it's possible, I absolutely think it's desirable and I think that we have said to all the parties that we are here to facilitate any discussions."
It follows comments by former chancellor Alistair Darling - who leads the pro-UK Better Together campaign - that any major change to devolution will have to feature in party manifestos.
In an interview with Holyrood magazine, Mr Darling said: "If you want anything more than a fairly minor change to the constitutional arrangement, then at some point you are going to have to ask the rest of the UK, which means that all the parties in a general election would have to have in their manifesto what they would intend to do."
The SNP said Mr Darling's remarks show that the promise of more powers in return for a No vote cannot be guaranteed.
Kenneth Gibson, an SNP MSP and convener of the Scottish Parliament's Finance Committee, said: "It is now clearer than ever that only independence will give us the tools we need to become a more prosperous and fairer country."