Michael Bublé on Simon Cowell, Gordon Ramsay and being a sensitive guy

But off stage he ping-pongs between confessions of sappiness (“When I have kids it won’t be a change. I’ve always been really sentimental and soft that way”) and mickeytaking bonhomie. To clarify: good-time-guy Bublé is joking – mostly – about Ramsay, but not about Cowell, with whom there is a little history…

In 2007 Bublé appeared on American Idol. “I had to sing Call Me Irresponsible in front of 20 million people. And the first thing I saw when I got on stage was Simon Cowell. I sang about four lines and he looked at me and did this [Bublé rolls his eyes in a Cowell gesture of dream-crushing dismissal] and that was it, I was done. It killed me. My confidence dropped.

“Maybe Cheryl Cole gets a little quiet and more demure when she loses her confidence. But I become aloof. I get the attitude of, ‘Oh really? Well, f * you.’ And,” he grins, “if you watch the clip on YouTube, I’m so aloof I look bored.

"And it became quite a thing for me in America because all the news agencies started to report that I was drunk. But I’m such a control freak I would never drink before going on stage.”

So in reality you were just sticking two fingers up to “Nasty” Simon?

“Yup! But years later, I’m talking to Dannii Minogue, and I told her the story. She goes and tells him, and comes back saying this: the man didn’t even know he did it. He was just probably sitting on his fifth hour of the show going, ‘Kill me now… and I’ve got to go to the bathroom.’

"But I’m so sensitive I took it as a rejection. Anyway,” Bublé beams, “every time I’ve ever talked to him since then he’s been incredibly nice.”

Then there is his celebrity chum, Gordon Ramsay. Bublé has been trying to wrangle a guest turn from the fiery chef on his American Christmas TV special.

“I wanted him to film a short where he teaches me to cook a gingerbread house but ends up calling me an idiot,” says Bublé, who earlier this year married Luisana Lopilato, the new “face” of Ultimo lingerie.

“And I wanted him to go nuts on me then I finish just looking at the camera, crying…”

Already during our free-roaming interview, Bublé – fortified by a bucket-sized soy latte brought by an assistant – has applied similar tough-love to another alpha male, his oldest friend from high school.

“He’s a good man but he’s not a warm guy,” he says with the brutal honesty of a lifelong pal. “Not that he’s cold, but he’s not a sympathetic character.”

This is the confidant who, when Bublé “went through the thing with Em [his split with British actress Emily Blunt in 2008] was my best friend”. Reeling from the break-up, the man with Sinatra’s pipes and a football player’s potty-mouth wailed heartbroken obscenities.

"And my buddy went, ‘Get over it! Let’s go get laid, man.’ That,” smiles the singer, “was basically his advice.”

In truth he loves his pal, loves Ramsay, and even loves Gino D’Acampo, the chef he roped in for his other festive special, Home for Christmas, ITV’s musical winter wonderland that co-stars Gary Barlow, Kelly Rowland and Dawn French.

Watch the “old school” light-entertainment extravaganza and you’ll laugh, you’ll cry, you’ll wonder if Val Doonican will pop up next. Such are the endeavours multi-tasking pop stars must undertake to promote their music...

Michael Bublé: Home for Christmas is on ITV1 tomorrow night at 9pm.