* Cameron visits Scotland to beg Scots to keep the UK
* Party leaders Miliband, Clegg also speak in Scotland
* Sterling hits a fresh 10-month low after online poll (Adds comments by Bank of England Governor Carney)
By Angus MacSwan
EDINBURGH, Sept 10 (Reuters) - British Prime Minister David Cameron on Wednesday begged Scots not to rip apart the United Kingdom’s “family of nations”, flying to Scotland to man the barricades against a surge in support for independence eight days before a referendum.
Cameron appealed to Scots to use their heads and their hearts when they voted on Sept. 18. He reminded them of their shared history and bonds with England, Wales and Northern Ireland - twice evoking World War Two and the fight against Hitler.
He also warned that an independent Scotland could not keep the pound currency, jobs would head south, and the country’s security be weakened.
“I would be heartbroken if this family of nations was torn apart,” said Cameron, speaking to staff of the Scottish Widows financial institution in the capital Edinburgh.
Cameron’s visit was a sign of the panic that has gripped the British ruling elite over the possible disintegration of the 307-year-old union since two polls in the past showed the campaign for independence, led by Alex Salmond’s Scottish National Party, gaining support to run neck-and-neck with the “No” campaign, which until a few weeks ago was looking comfortably ahead.
There was some relief for unionists when a poll released on Wednesday evening showed 53 percent of Scots would vote against a split, with 47 percent intending to opt for independence - unchanged from its last survey on Aug. 28.
The figures from the poll, carried out by Survation for the Daily Record newspaper, excluded 10 percent of undecided.
British deputy prime minister Nick Clegg, who leads the Liberal Democrats, and opposition Labour Party leader Ed Miliband also crossed the border on Wednesday to shore up support. All three parties have offered Scotland greater autonomy as an enticement to vote against independence.
The prime minister, whose job may be on the line if he loses Scotland, warned Scots a vote for secession would be forever.
“I think people can feel it is a bit like a general election, that you make a decision and five years later you can make another decision if you are fed up with the effing Tories, give them a kick and then maybe we’ll think again. This is totally different to a general election: this a decision about not the next five years but a decision about the next century,” he said.
Cameron has until now been largely absent from the debate after conceding that his privileged background and centre-right politics mean he is not the best person to win over Scots, who returned just one Conservative lawmaker out of 59 in 2010.
He made no street appearances in his visit to Edinburgh.
“David Cameron is a swear word up here,” said one security guard, asking not to be named.
That comment echoed the sentiment among pro-independence Scots that they are ruled from London by a government they did not choose - a central tenet of the independence drive.
The “Yes” camp says it wants to build a fairer society with Scotland’s interests at the forefront. Opponents of independence say Scotland is stronger and more secure within the United Kingdom, and a separate country would struggle economically.
The ramifications of a split could be immense given the United Kingdom’s position as a G8 economy, a leading member of NATO and the European Union, and permanent member of the U.N. Security Council. U.S. President Barack Obama and other world leaders have said they want Britain to stay together.
Cameron held out the promise of more power for Scotland if Scots voted “No”.
“It really will be the best of both worlds,” he said.
“Scotland is a nation, an incredible nation, strong, proud, with an extraordinary history but also part a family of nations. Please don’t think that the rest of the United Kingdom is indifferent. We care passionately.”
Salmond said the visits were a sign of panic that would only help the secessionist cause. Independence supporter James Curry, 33, said in Edinburgh he found the visits by politicians from London “insulting and patronising”.
“They should’ve been up here ages ago. Instead, they’re having a wee day trip,” he said. “There’s so much at stake, and it seems so real already, I just hope we make it.”
Labour’s Miliband meanwhile went to the town of Cumbernauld to campaign for Scotland staying in the union.
Labour supporters are seen as a vital constituency in the fight, given the dearth of Conservatives in Scotland, and if enough reject the party line it could tip the balance.
The loss of Scottish Labour MPs in Westminster should Scotland become independent would also seriously affect its election prospects south of the border.
Miliband promised that Labour would meet Scottish aspirations for a just, fairer society. He said working-class solidarity went across the border and noted that six Scottish trade unions had come out against independence.
“The people of Scotland, whether they intend to vote no or yes, have established beyond doubt in this campaign that there needs to be profound economic and political change. This thirst for change is shared across the United Kingdom.”
Saying that his father served in Scotland in World War Two, Miliband said. “So many, across the United Kingdom, will have their own connections of friendship and family with Scotland ... Please stay with us.”
The surge in support for independence over recent weeks has also discomfited investors. Sterling hit a 10-month low against the dollar and a three-month low against the euro on Wednesday, with traders citing an unverified web poll conducted by a blogger that gave the “Yes” camp a strong lead.
Some major companies with Scottish exposure cautioned about the risks of secession: Standard Life said it could transfer business to England, while BP CEO Bob Dudley said the future of North Sea oil was best served by keeping the United Kingdom together.
Following a vote for independence, London and Edinburgh would face 18 months of talks on how to carve up everything from North Sea oil and the pound to EU membership and Britain’s main nuclear submarine base at Faslane.
Bank of England Governor Mark Carney said that a new centrla bank in and independent Scotland would need big stockpiles of sterling if the coutnry opted to adopt the pound without an agreement with the rest of the United Kingdom. He also said it was likely that economic borders would build up between an independent Scotland and the rest of the UK.
The referendum - the biggest internal challenge to the United Kingdom since Irish independence almost a century ago - has electrified Scotland. On streets, in pubs and in meeting halls from the Highlands to the windswept islands of the Atlantic, independence is being debated with passion.
Bookshops are full of referendum guides and tracts for and against. The Scotsman newspaper published six pages of letters on the vote on Wednesday.
“Do we wish to become a small, successful, independent state free to develop our own way of life and find our way in the family of nations? Or would we rather continue as a small appendage of a once glorious but now declining power punching above our weight in hopeless wars like Afghanistan ... while at home constructing one of the most unequal societies in the world,” wrote “Yes” supporter John Slee of Gullane.
Other letter writers said the SNP’s economic figures just didn’t add up, particularly the funding for public spending.
“The ‘Yes’ campaign’s spin doctors are successfully piping our economy off a cliff,” wrote Hugo Cannon of Edinburgh. (Additional reporting by Guy Faulconbridge, Michael Holden, Kate Holton, Andy Bruce, Kylie MacLellan and Jemima Kelly in London and Alistair Smout in Edinburgh; Editing by Will Waterman)