The leaking of a document which claims Nicola Sturgeon would prefer David Cameron to remain in Downing Street is “not acceptable”, the Prime Minister has said.
The Conservative leader said he “abhors” such private memos being made public as he vowed to “get to the bottom” of how the official document was passed to The Daily Telegraph newspaper.
Head of the civil service, Sir Jeremy Heywood, has launched an inquiry into the circumstances surrounding the leak, which came from the Scotland Office, in the aftermath of the First Minister saying the story was “100% untrue”.
Mr Cameron said: “I didn’t see this document. I abhor the leaking of documents. We need to be able to have private, diplomatic conversations.
“I see as Prime Minister every day the importance of that protocol. So there is a proper leak inquiry going on and I want to tell you it really is proper. I want to get to the bottom of this.
“This is not acceptable behaviour and I hope we get to the bottom of who did this.
“As for what Nicola Sturgeon said, I don’t know. My view for the last four years has been that Ed Miliband is not up to the job of being prime minister and I’m always delighted when anyone joins me in that widely-held opinion.”
The leaked memo reports Ms Sturgeon told the French ambassador to the UK, Sylvie Bermann, that she preferred Mr Cameron over Ed Miliband, who she felt was not prime minister material. Both Mr Bermann and the French consul general have also said the memo is inaccurate.
Liberal Democrat Alistair Carmichael has said he knows who wrote the memo, but not who leaked it.
During a briefing with journalists in Edinburgh, the Prime Minister reiterated his warning about a Labour government propped up by the SNP.
He said: “Nicola Sturgeon wants two things. She wants to break up the United Kingdom. I totally oppose that. And she wants more borrowing, more spending, more taxes, more debt, unlimited welfare and I totally oppose that.
“I think she’s wrong on the two big questions of our time. So that’s why we are fighting such a vigorous campaign.”