Former Northern Ireland Secretary Peter Hain has proposed a new Act of Union aimed at keeping the UK together.
It would agree which responsibilities should remain with Westminster and which should be controlled at Stormont and other devolved legislatures in Scotland and Wales.
Lord Hain was Northern Ireland Secretary in Tony Blair’s Labour Government from 2005-2007. He joined a group of senior parliamentarians including former Ulster Unionist South Antrim MP David Burnside to advance draft measures intended to stabilise the union after the Brexit vote.
They said: “The draft Act does not turn back the historic process of devolution, but rather provides a new over-arching constitutional framework to address the present unintended imbalances and inconsistencies, and to stop the threat of separation from Scotland.
“The Act would provide a period of constitutional stability following the trauma created by the recent vote for Brexit.”
Scottish First Minister Nicola Sturgeon has said another independence referendum is “highly likely”.
Under the blueprint promoted by Lord Hain powers like national security, defence and foreign policy would reside with Westminster.
“Rather than Westminster reacting under pressure for more devolution, the Act would provide that the four countries of the United Kingdom should agree what powers are to be transferred and reserved by Westminster ... and what should be governed locally.”
The draft Act also contains options for the governance of England, including a directly elected English parliament sitting in the House of Commons or an expansion of regional devolution similar to that seen recently in Manchester.
It also provides for the House of Lords to be replaced by a new elected chamber to represent a new federation of the UK.