Nationalist stereotypes about the British Empire and the UK being "worn out" need to be dispelled to win over young Scots and prevent Scottish independence, according to a think tank.

A report by the Council on Geostrategy said many Scottish nationalists equate "Britain with empire and empire with evil", with independence part of "the progressive arc of history".

Under this narrative, it said the break-up of the UK would be "an act of national repentance from an oppressive imperial past" with "salvation" being achieved through EU membership.

But the authors, Prof Nigel Biggar and Prof Doug Stokes, concluded: "In short, if the disintegration of the UK is to be prevented, faith in Britain needs to be revived.

"We need to remember what the UK is good for and that whereas German taxpayers are adamantly opposed to fiscal transfers to the Greeks, Londoners hardly bat an eyelid at the redistribution of ‘their’ taxes to Scotland."

In contrast, they said independence negotiations "risk that resentment between the English and the Scots would rise to levels not seen since the 18th century".

They said arguments that independence would be a major act of economic self-harm or that Nicola Sturgeon’s Covid performance has been little better than Boris Johnson’s would probably move some older floating voters.

But they added: "For younger, idealistic Scots it is necessary to recover and develop a morally attractive story about the UK with which they would want to identify. The nationalist stereotype of post-Brexit, Tory Britain as worn-out, xenophobic, and devoted to impoverishing the poor needs to be confounded."

The report argued this could be achieved using a "sophisticated social media strategy" that distils Britain’s real story into "accessible and entertaining social media content such as short videos and memes".

Prof Biggar is Regius professor of moral and pastoral theology at Christ Church, Oxford, and Prof Stokes is professor in international security and academic director of the Strategy and Security Institute at the University of Exeter.

Their report follows a series of opinion polls showing more than two-thirds of younger Scots now support Scottish separation. However, they argued that Britain has a "good story" to tell them, with the UK Government pursuing an "ambitious" green agenda and planning a high-profile global role.

They also warned that independence would be a "propaganda coup" for Russia and China, with Britain’s "soft power" on the international stage damaged and increasing calls for the UK to cede its position as one of the permanent five members of the UN Security Council.