Cameron last month opted out of a re-negotiation of the EU's Lisbon Treaty on which this guidance is based.
Standard procedure for external accession candidates such as Croatia, which enters in 2013, involves the unanimous backing of all EU governments.
The Scottish National Party (SNP) leader wants to hold it in late 2014 around the 700th anniversary of the battle of Bannockburn, a famous victory over England better known today for its portrayal in the film "Braveheart."
Salmond wants to use a distinct electoral roll -- granting votes based on residency rights at the time and lowering the voting age to cash in on what polls show is majority backing for independence among young and immigrant voters.
He also wants to offer a middle way characterised as 'independence-lite' that would see Scotland retain ties to the UK such as shared military endeavour.
Cameron, though, wants a sudden-death poll controlled by London, with a single question asking voters if they want to be 'in or out' of the 305-year-old political union joining Scotland and England.
He also opposes lowering the voting age from 18 to 16.
EU officials focused firmly on trying to resolve the eurozone debt crisis are not actively planning for the break-up of Britain.
Many hope the Scottish referendum will return a compromise position granting fiscal autonomy -- the flipside of 'independence-lite,' known as 'devolution max.'
Officials refuse to go public on Scotland fearing a green light for other wealthy sub-states like Bavaria, Catalonia or Flanders.