Henry McLeish, the former Labour First Minister, has criticised his party north and south of the Border and, by implication, Gordon Brown for failing to understand the seriousness of the threat to the Union from a popular and populist SNP government.

Mr McLeish, in an article in The Times today, says that Labour has mounted “no serious defence of the Union” and is failing to recognise that the Union needs serious reform. “Superficial solutions are being offered to substantial constitutional problems,” he writes.

He says that during the first ten years of devolution Scottish Labour has failed to accept a different political identity and to develop a new political culture.

“A new political strategy makes sense and would appeal to a Scottish electorate supportive of the new SNP Government's populism, but consistently wary of independence,” he adds.

Mr McLeish, who led Labour at Holyrood between 2000 and 2001, argues that to deny the Union is in need of reform may contribute to the constitutional crisis that Labour at Westminster seeks to avoid.

“The main threat to the Union will not be the advance of Nationalism but failures at the heart of Unionism and misjudgements by the Unionist parties. The impetus for the breakup of the Union may be created at the heart of the Union itself,” he says.

Labour has to breathe new life into the Union to confront the SNP and Mr McLeish bemoans what he says has been a refusal by the candidates in the present Labour leadership contest in Scotland to consider that issue.

He asks: “Why has Labour failed to embrace a more autonomous Scotland and a radically different United Kingdom? More to the point, why are these arguments not central to Labour's leadership contest in Scotland?”

He calls on Labour to develop a strategy reflecting the political and constitutional changes taking place in Europe and the need to look again at the Treaty of Union and the Scotland Act - “aiming to review and reform (not repeal and remove, although the Union does need a radical makeover).” Labour should use the opportunity to make “a powerful statement about nationality, not nationalism; identity, not isolationism; and diversity, not division,” he adds.

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