Nationalist movements in Wales and Scotland are losing the arguments in the UK as people seek to 'bang the door shut on a decade of division', former Prime Minister Gordon Brown has argued.

Sports stars like Emma Raducanu provide a powerful image of the diversity of modern Britain and show that to be British does not mean having one identity, Mr Brown wrote in an article for the New Statesman.

"For years we have been told that a more strongly-felt Englishness, Scottishness and Welshness would weaken Britishness and foreshadow the end of the Union," he wrote.

"That is wrong. Attempts by some Unionists to subsume Englishness, Scottishness and Welshness in an all-consuming Britishness will not succeed. Diversity is not a threat, but a multinational state’s USP.

"Unity does not require uniformity and solidarity does not demand the elimination of regional and national differences. To be British does not mean having one identity. Citizens can be comfortably Muslim, English and British.

"Only a minority now believe that the main characteristic of being British is that you were born in Britain. It is possible to be born in Canada of Romanian and Chinese parents and be, like Emma Raducanu, a new British sporting icon. Within these islands, to rephrase Tennyson, all that we have met are a part of each of us."

The former Labour Party leader, who was chancellor of the exchequer under Tony Blair from 1997 to 2007, went on to criticise Boris Johnson's attempts to save the union by denying national differences.

He said: "That is why Boris Johnson’s “muscular unionism” simply plays into the hands of Nicola Sturgeon and her plans to provoke a constitutional crisis next year. Describing the UK as “one nation”, he is abandoning the bigger idea – and better reality – that we are a “family of nations”.

"He wants to badge new Scottish roads and bridges as British, as if hoisting more Union Jacks will make people decide they are only British and not also Scottish or Welsh. Once the champion of more powers for London, he now sees devolution outside London as “a disaster."

Mr Brown went on to argue that millions of Welsh, Scots and English people donate blood and organs every year not caring which nation they go to, only that they save a person in need.

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