The Prime Minister did not discuss his plan for a referendum on taking the UK out of the European Union (EU) with the minister tasked with battling Scottish independence, despite Europe being a key plank in the anti-independence campaign.
Scottish Secretary Michael Moore said David Cameron was speaking "as the leader of the Conservative Party" when he pledged to hold an in/out referendum on the EU in 2017 if the Tories win the next general election.
Mr Moore stressed that he is "very comfortable with all of the arguments" on the EU, and stressed that as a Liberal Democrat he will be campaigning to remain in the EU.
He repeated his belief that independence is the real threat to Scotland's future in Europe, insisting that a yes vote in the referendum would eject Scotland from the EU and force it to reapply under uncertain terms.
Speaking at an energy summit in Edinburgh, Mr Moore said: "The Prime Minister spoke yesterday as the leader of the Conservative Party setting out his vision for his manifesto for the next general election, which is entirely right.
"We don't consult each other as parties within the coalition about what will be in our respective manifestos, that will be for us to determine.
"My own view as a Liberal Democrat is that Scotland is stronger within the UK, and the UK is stronger within the EU, and I will be doing everything that I can to make sure that Scotland remains part of the UK and the UK stays part of Europe.
"I'm very comfortable with all of the arguments, because what the SNP and others can't escape is that we have an actual real referendum coming up in roughly 18 months time where the impact of a vote to leave the UK would be to put us outside Europe and require us to negotiate our way back in on terms and conditions that we can only guess at.
"So, the muddle and confusion of the SNP over their European policy is the real issue for us here in Scotland, and that's what I am focused on."