Voters in Scotland must be offered an alternative vision for the country beyond the "dreamland" of independence or increasingly bitter arguments between Holyrood and Westminster, a former senior civil servant has claimed.
Philip Rycroft, a former chief civil servant in the Department for Exiting the European Union, suggested that "leaving one Union does not have to lead to the foundering of another".
Addressing the David Hume Institute in Edinburgh this week, Rycroft said a new relationship between the Scottish and UK governments was needed to secure the future of the Union.
The former civil servant worked for the Scottish Office for a decade before moving to the newly-established Scottish Executive in 1999.
"As things stand, people in Scotland really only have two imagined futures before them, one the dreamland of an independent state, the other an extrapolation of a squabble-some present into a dystopia of increasingly acrimonious disputes between two governments, bent on different paths," he said.
"That does not have to be it. Hard as it may be in these difficult times, people in Scotland and in the rest of the UK deserve a richer debate, a recognition that there are other choices, that out of the shattering Brexit mayhem could emerge a different dispensation for the UK.
"Leaving one Union does not have to lead to the foundering of another. But, unless the next Prime Minister, whoever that might be, puts this high up their agenda, that might be their legacy."
The Scottish Government has stepped up its demands to hold a second referendum on independence in response to the continued constitutional uncertainy caused by Brexit.
Current polls suggest the SNP can expect to make gains at any snap election held before the end of the year.
Mr Rycroft suggested a new department for the Union could be required to make the case for the UK in the devolved nations.
“There is a case for a department of the Union, embracing the whole of the current UK Governance Group and the Northern Ireland Office, to give greater heft to the management of constitutional and devolution issues," he said.
"That could be buttressed by an enhanced place for the handling of devolution in the Cabinet committee structure.
"But the key would be a serious overhaul of the system of inter-governmental relations, to bring the devolved governments earlier and deeper into the counsels of the UK government. With seriousness of purpose, there are structures to build on in the JMC itself – the form less important than the substance of the discussion.
"There is an offer to be made, but it would have to be made in earnest. With levels of trust so low, it would inevitably take time before people in Scotland were getting the sense that their two governments had finally got round to working together on the building of a common future."