Sidestepping any facts, Page offers instead an irritated broadside at biographers perpetuating a lurid fascination with the bad stuff: “Wall’s just writing a book designed to cash in on something he didn’t have anything to do with. He wasn’t a creative force in Led Zep. I’m at something of a disadvantage because I haven’t chosen to read that book, but I hear it’s totally distorted from people who do know about Led Zeppelin.”

But doesn’t he accept that people are interested in the darker side of the Zep legend? “In this day and age there is a sensation that people feed off — towards that aspect of things — with a voracious appetite. It’ll be interesting to see what’s more important at the end of the day — the salacious gossip or the music. I know what I went into it for in the first place. What’s important about Led Zeppelin is the music.”

By now I feel that my questions are starting to goad him — an inquiry into the possible direction the next Zep album might have taken had Bonham not died is met, quick as a flash, with a curt: “I don’t know because we didn’t do it.” He is far more voluble about that 2007 Zeppelin reunion gig, reserving special praise for Jason Bonham, who played in the drum stool vacated by his late father. “It’s great that we did it. I look back on that night with a great amount of fondness, but Jason was the hero. For me that gig was about him.”

Since then, Plant and Jones have forged ahead in new directions — Jones most recently in the supergroup Them Crooked Vultures (“It has great promise, but I’ve only heard what they did on Jonathan Ross,” Page says. “I need to really listen to what they’ve done”) and Plant with the country siren Alison Krauss on the Grammy-laden Raising Sand. It would have taken only an OK from the reluctant Plant for that Zep tour to have been on. Indeed, Page’s will for the tour was so strong that reportedly there was even a brief, mad idea to find a replacement singer.

The area is suddenly sensitive, Page saying that he and Plant get on “fine” and stressing that “the one thing I don’t want to do is to try to make it look as though I’m trying to be controversial about what they’re doing. Whatever anyone else does is fine. Theirs [Plant and Krauss’s] was a really acclaimed album, and it’s really good.”

Understandably, he is more enthusiastic about discussing his own plans for solo work, which would be his first since 1988. “I think it’s very important to do some musical statements with new material and that’s exactly what I plan to do over the forthcoming year. Musically it will be a different picture in quite a radical frame, I hope. I’d like to try some ambitious projects. But we’ll see.”

I can’t help but sense that this hitherto undisclosed news — exciting as it is for rock fans — comes with a slight sense of resignation too. As if to emphasise that he has closure on the idea of a Zeppelin reunion, he finishes up with further warm, wistful remarks of how Zeppelin was “a remarkable time and the fact that we could remanifest it again was terrific”.

Today, his once softly handsome features somewhat creased, he has the air of a coolly distinguished elder; he was even appointed OBE in 2005 for charity work on behalf of street children in Brazil (a concern he set up with his third and current wife, Jimena Gomez-Paratcha, 37, with whom he has had two children).

He bids me such a disarmingly affable farewell that the idea of some Prince of Darkness on the other end of the line couldn’t be more absurd. If the glory of his legendary band may for ever define him, fulfil him and perhaps frustrate him, Page really couldn’t be more of a gentleman about it all. And that posthumous book? Maybe some things remain most powerful when left in the dark.

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