‘Barack Obama tonight urged Scottish voters not to break apart ‘one of the closest allies we’ll ever have’ by voting for independence on Thursday.
The dramatic intervention, just three days before Scotland goes to the polls, will infuriate Alex Salmond – with the battle for independence set to be decided by the smallest of margins.
Up to half a million voters remain undecided – with concerns over the future of Scotland’s place in major international organisations like the EU, Nato and the UN still hotly debated.
Mr Obama’s spokesman Josh Earnest said: ‘From the outside, the United States has a deep interest in ensuring that one of the closest allies we’ll ever have remains strong, robust, united and an effective partner of the United States.’
The remarks came after Nato secretary general Anders Fogh Rasmussen confirmed Scotland would have to reapply to join the military alliance – and stressed that to do every members would have to agree.
He said: ‘In case that Scotland voted in favour of independence then Scotland would have to apply for membership of Nato as a new independent state. A decision on accession would have to be taken by unanimity, by consensus as always in Nato.’
The double salvo against independence comes amid warning that the US would vigorously oppose the Alex Salmond’s plan to move Britain’s Trident nuclear submarines from the Clyde after independence.
Britain’s nuclear capability is key strand of Nato’s military defence and any threat would spark fury in Washington.
Earlier this year Mr Obama used the 70th anniversary of the D-Day landings to praise the United Kingdom and warn against Scottish separatism.
Speaking alongside David Cameron, Mr Obama said: ‘I would say that the United Kingdom has been an extraordinary partner to us.
‘From the outside at least, it looks like things have worked pretty well.’
The British people will make the ‘right decision’ in an in-out referendum, he said.
‘We obviously have a deep interest in making sure one of the closest allies we will ever remains a strong, robust, united and effective partner.’ ‘