Has Out already been ruled out? Or in plainer but more cumbersome language, has David Cameron already put those Conservatives who want to leave the European Union at an impossible disadvantage, by forcing them to delay the start of their referendum campaign until the outcome of his renegotiation is known?

David Campbell Bannerman MEP – or DCB, as he will be called for the sake of brevity in this interview – does not think so. As co-chair of Conservatives for Britain, the new Eurosceptic group led at Westminster by Steve Baker, he contends that Cameron’s renegotiation is essential, in order to show floating voters (the majority) that the possibilities of reforming the EU have been exhausted.

DCB has an exotic past. His great great great uncle, Sir Henry Campbell-Bannerman, served as Prime Minister from 1905-08, and was the last Liberal leader to win an overall majority.

And although DCB started out in the Conservative Party, he had a spell as a UKIP MEP before returning to the Tory fold. DCB will tomorrow meet his fellow Tory MEPs, and expects that a majority of them will join Conservatives for Britain.

This interview was carried out in the St Pancras Hotel, the sublime Gothic edifice designed by George Gilbert Scott. The plan was to drink coffee, but on discovering there was a minimum charge of £12.50 a head, DCB agreed, in a spirit of consensus, to have a gin and tonic.

ConHome ordered a cocktail called a Britz, but on being informed, rather ominously, that one of the ingredients had run out, fell back on a cup of champagne punch.

During the interview, DCB regrets that UKIP has “tainted” the Out campaign by concentrating too much on immigration, warns that the European Commission will “play dirty” during the referendum campaign, and says what a good Out leader Boris Johnson would make.

ConHome: “Cameron’s made it very difficult for the No campaign, hasn’t he, because you have in fairness to wait and see what he can get.”

DCB: “I think the timing of it is very important. I think the Electoral Commission is right. It says there has to be a six-month break between when the Bill passes and when the referendum takes place, which would rule out May 2016, assuming it gets through at Christmas, which I’ve heard is likely. I think we really need to look at September, October 2016.”

ConHome: “But you’re slightly ham-strung, aren’t you? Cameron has actually put a spoke in the No campaign’s wheel by this way of going about things.”

DCB: “Well I suppose people are free to come out and campaign for Out straight away, but I think you have to recognise that it’s not just about the Conservative Party. The reality is that 70 per cent of people are undecided, so there’s an awful lot of floating voters.

“If you want Out, then a lot of those floating voters will want to see an attempt at renegotiation first, to see what the alternative is. Really the pressure’s on the EU. If the EU really doesn’t play ball, and is too arrogant or dismissive, there could be quite a decisive move towards Out as a result of that.

“So it’s not just a technique to delay the campaign, and I do believe it’s a genuine exercise, it’s not a charade. Whatever comes through has to be saleable to the British people, has to be a fundamental change.

“I think people will see through a shallow deal, which they didn’t do in 1975, but if that was tried again, people would see through it, it would be counter-productive.”

ConHome: “Owen Paterson, in his piece for the Mail on Sunday, had this arresting phrase: ‘The British state, in cahoots with the Brussels machine, will be able to fix the vote in its favour.’”

DCB: “Well there is a real issue, and I’m going to put down quite a few parliamentary questions on what the Commission will be doing in terms of how it spends its money. Because the Commission’s tentacles are in all sorts of areas.

“For example, a lot of people do not realise that it funds non-governmental organisations like Friends of the Earth: half of its funding comes from the EU. So if Friends of the Earth suddenly sits up in the middle of a referendum campaign and says, ‘Well look, you know, we really must be part of the EU’, you have to question their motives.”

ConHome: “Half of it?”

DCB: “It’s not widely known. Greenpeace to their credit turned it down. But the RSPB also receives an awful lot of money. Dan Hannan has a lot of data on this. The CBI has received about £800,000 from the EU for reports.

“So it’s not just the British government throwing its money around in the last days. If the EU suddenly decides that Friends of the Earth requires a major top-up, how does that influence things?”

ConHome: “So there has to be a purdah period, when no one can do this.”

DCB: “I really do think so. If you look at their track record in forcing the Irish to vote twice on the Lisbon Treaty, after six months they had to vote again, which was not constitutional, having thrown money at them. I think they will play dirty.

“And so I want to ask a lot of questions about how the EU can interact with our referendum. We need a fair referendum or there could be huge resentment building up against our party and against the Government, which is not healthy.”

ConHome: “What role should your old comrade Farage play in this?”

DCB: “Well in an Out vote, I mean, you’re not going to shut him up [laughter]. He deserves a role in the Out campaign. A big role. But I don’t think he should be the face of that campaign, because it has to appeal across a much broader spectrum.

“And I think UKIP has actually tainted the Out Tories, by putting too much emphasis on immigration. I think it’s actually damaged the Out cause, it has dropped back during this election campaign, the Out cause.

“Nigel loves public meetings, and he’s brilliant at them. He’s actually re-engaged people into public meetings. It used to be a lost art. But he’s still able to draw hundreds, and that’s something I can imagine him doing.”

ConHome: “Do you have someone in mind to be the face of the Out campaign?”

DCB: “There’s a lot of discussion going on. We think probably a woman, and probably a businesswoman. But I think the Out cause can win.”

ConHome: “What is the Conservatives for Britain agenda?”

DCB: “We believe we must get fundamental change. Fundamental is the key word, and it’s the word the Prime Minister used on 23rd March this year in Parliament. He did talk about fundamental change, and we’re supporting him on that.

“But our fear is if we do not get fundamental change, renegotiation will not be saleable to the British people, and there are up to a hundred MPs, probably more, who are prepared to back the Out campaign if renegotiation doesn’t go far enough.”

ConHome: “What is your personal position?”

DCB: “I’ve always believed personally we’d be better off out of the EU, but I respect that Conservatives for Britain is different, it has people who want to see how renegotiation goes, those that want to stay in the EU, so it’s a much broader church, the Conservatives for Britain. It is not the nascent Out campaign.

“EEA within the European Union would be enough to persuade me. I’d have a Norwegian-type deal with some immigration controls as well, but within the EU.

“The feedback we get from federalists, interestingly, is they’d rather we have a separate deal than open up, as they see it, the Pandora’s Box of renegotiation of EU powers. Because they’re worried that whatever Britain gets, Denmark will want, the Irish or the Dutch.”

ConHome: “You haven’t been burned in effigy lately?”

DCB: “As far as I know, it was only that one occasion that I really made it. Yes, obviously, I understand. People talk about loyalty.

“My loyalty is always to my country, my country first. When I was at UKIP I was always regarded as being a Conservative and always wanted to come to a deal with the Conservatives.

“I didn’t see UKIP becoming a government on its own or whatever. It was always a means of articulating a strong, passionate view about safeguarding our country, and of course that has played very well and many Conservatives backed us at that time.”

ConHome: “Boris Johnson was mentioned by some people as a possible leader of the Out campaign.”

DCB: “I think that would be very interesting. If Boris were to lead the Out campaign it would give it a huge boost, and I think you would be into a very serious contest then.

“Because Boris, I helped him twice in the London campaign, and I spent all my time talking to Labour and Lib Dem voters, telephone canvassing, all of which wouldn’t touch the Conservative Party but liked Boris and liked what he stood for.

“So Boris has this ability to reach out across parties. And others close to him would I think follow. There are MPs that are close to him. James Cleverly MP is involved in Conservatives for Britain.”

ConHome: “How did you come to be the co-chair of Conservatives for Britain?”

DCB: “Well we’ve had various discussions with people that may get involved in the bigger campaign. They suggested –  I know Steve Baker, we met in Iceland funnily enough, on an AECR trip, and it was suggested we get together.

“He’s done a fantastic job of really exciting up to a hundred MPs in this project, and I think that’s a great achievement. He’s doing the Westminster end, but I’m meeting on Wednesday morning with the MEPs. We’ve got about 11 or 12 interested, of the 19 Conservative MEPs.”