Speaking at last night's Scottish Conservative reception at his party conference, the Prime Minister said: "I want the message to go out from this conference here in Manchester, in England, among the Conservatives, to people in Scotland: we want you to stay, we value Scotland as part of the United Kingdom."
He stressed how he wanted the rest of the UK to "shout loudly and proudly that we will be better off with you with us".
Earlier, Mr Cameron mocked Alex Salmond over his demand for a live TV head to head debate, saying that he had a "new pen pal, writing me letters on an almost daily basis".
But he insisted that the First Minister could try as "hard as he likes" to deflect matters but it was only right he, as leader of the Yes campaign, debate with Better Together leader Alistair Darling. The SNP said that was "ridiculous".
Politics: Page 6