David Cameron yesterday pledged never to give in to “narrow English nationalism” as he presented a clear challenge to those in his party who believe that the Tories would be better off concentrating their efforts south of the Border and jettisoning their support for the 300-year-old Union between England and Scotland.

The Conservative leader, in a speech to party activists in Edinburgh, indicated that he had no interest in becoming the Prime Minister of England alone, declaring: “We are a party of the Union and, as long as I lead it, that is how it will stay.”

Mr Cameron criticised nationalists both sides of the Border, saying that he saw it as his job to defeat “the ugly stain of separatism that is seeping through the Union flag”. He acknowledged that it was essential for answers be found to issues such as the Barnett Formula and the West Lothian Question, and he pledged to address them without putting the Union at risk.

In a speech delivered only yards from the new Scottish Parliament building, Mr Cameron sought to defuse criticism that by backing “English votes for English laws” at Westminster, the Tories were tacitly giving up on the Union and any prospect of future electoral success in Scotland, where they have only one MP. “We must not allow the legitimate and affectionate doubling up of patriotic pride to be pushed aside by a coarse and casual nationalism,” he said.

Mr Cameron also turned his fire on Gordon Brown, lampooning the Prime Minister’s efforts to sell the concept of British-ness. “It is vital we get this right,” Mr Cameron said. “[Brown] approaches the whole question of national identity like a sort of brand manager trying to launch a new product on the market. So we have citizen’s juries to decide what it means to be British. We have a competition to come up with a motto for Britain.”

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