David Cameron virtually admitted yesterday his party could not expect to win more than a handful of seats in Scotland at the next general election but promised that he would never-theless treat the country with “respect”.

The Conservative leader, addressing the Scottish Tory conference only hours after his party captured Crewe & Nantwich in a spectacular victory, appeared to accept the electoral reality north of the Border.

The Tories have only one MP from Scotland at present and even the most optimistic assessment says that they can expect to add four or five at the next election.

Mr Cameron's “respect” pledge could also be taken as an implicit criticism of the Thatcherite approach to Scotland. Margaret Thatcher was often attacked for not understanding why the Scots resented the destruction of their heavy industry in the Eighties and the imposition of the poll tax, leading them to decisively reject the Tories at election after election and also leading to the inexorable rise in support for devolution — a policy also rejected by Mrs Thatcher.

Mr Cameron told his Scottish party in Ayr: “To the people of Scotland, I make this guarantee. Whatever the outcome in Scotland at the next general election, a Conservative government will govern the whole of the United Kingdom, including Scotland, with respect.

“Whoever is Scotland's First Minister, I would be a Prime Minister who acts on the voice of the Scottish people and will work tirelessly for consent and consensus so we strengthen the Union.”

He also hinted that he would be prepared to act on growing demands for more powers for Holyrood, saying a Conservative government would “work to see how the devolution settlement can be improved upon ... so it builds on what we have and continues to deliver for the people of Scotland”.

He also derided Alex Salmond, the Nationalist First Minister, for having “a plan” to hold an independence referendum in autumn 2010 in the hope that a Cameron-led government would be by then unpopular in Scotland and thus build more support among Scots for separation from the rest of the UK.

He said: “I know you [Mr Salmond] think a Conservative government at Westminster will ignore what Scotland wants and needs and that you will use such claims to promote your separatist agenda.

“Think again. We've got the vision. We've got the ideas and we've got the ambition. We can be the force that defends the Union ... we can be the force that delivers on progressive ideals.”

Mr Cameron was also dismissive of recent Labour contortions over a referendum on independence after what he said was the “reckless” call by Wendy Alexander, the Scottish Labour leader, for an early vote on the issue — a call that met with a frosty reception from Gordon Brown and was subsequently dropped.

“It would be funny, if it wasn't so serious,” he said.

“Labour think they're being clever. What they've actually done is put the Union under greater threat. To play games by calling for a referendum right at the moment when people would take any opportunity to give the most unpopular Government in living memory a good kicking isn't clever, it isn't good politics, it isn't defending the Union. We should have none of it.”

Mr Cameron said that the Tories were “the party of the Union” and would defend the Union “because, heaven knows, Labour won't”.

He repeated his assertion from last year that “the ugly stain of separatism” was seeping through the Union flag and said that the Union was under attack as never before.

He said: “It's up to serious politicians to put their cards on the table. I don't want to be Prime Minister of England. I want to be Prime Minister of the United Kingdom — all of it, including Scotland. I will do everything and anything to keep our two countries as one.”

He claimed that the Scots had “no choice” between Labour “offering big state solutions” and the “disestablishment” SNP. Scots were “crying out”, Mr Cameron said, for a strong and moderate centre-right party that backed the Union, backed families, tackled poverty, unlocked social mobility and protected the planet.

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