It’s hard not to notice Salma Hayek’s bosoms. She is so very, very little, and though primly camouflaged this morning underneath her Gucci jacket and Balenciaga ruffle shirt, they do, as it were, precede her. On the other hand, given she is still breast-feeding (her daughter, Valentina, by the French businessman François-Henri Pinault, was born in September last year), perhaps that’s only to be expected. Wow. Breast-feeding for an entire year. I shouldn’t say this, but maybe that’s one of the reasons why she called off her wedding to the billionaire Pinault last July. I mean, that long? How does one possibly get anything else done? “Yeah, well, let me tell you it’s toff,” agrees Hayek, in that throaty Mexican accent of hers. “You don’t know what pain I’m in after two hours, how difficult it was at first. And by the way, the myth that says you lose all this weight when you breast-feed? That is sooo not true. Look,” she protests, grabbing her tummy and then reaching for the plate of biscuits the waiter has set down on the table, “it’s like, ‘Please, everyone, can you stop telling me I look really well?’ ”

It’s about 11 o’clock in the morning, and Hayek, 42, in town to promote her new role as an ambassador for Unicef, has just returned from the studios of This Morning, where Eamonn Holmes — the plonker — misheard her when she said she was part Lebanese, and thought she said “lesbian”. Hayek wasn’t fazed at all. This is, after all, the woman who took off her clothes in that famous elevator scene in Ugly Betty; the woman whom the American chat-show host Jimmy Kimmel immortally serenaded with: “I’m very hairy, you are a mummy, your name is Salma, I like salami”; the woman whom the funniest human being in the entire universe, Tina Fey, called personally to appear on her cult comedy television series, 30 Rock.

This is the woman, too, who tells me (after we’ve established our mutual love for the Greek island) that Mykonos’s famous pelican, which struts round the cobbled streets as a sort of tourist attraction, is sadly no longer with us. “Joo didn’t know?” she asks, those sphinxy, furry-lashed eyes widening in droll surprise. “Well it’s because someone f***ed it, poor thing, and I’ve never been able to get over it. Maybe you shouldn’t print that?”

Hayek and I first met eight years ago, on the eve of the Oscars in LA. It was right before she moved in with Edward Norton, the actor who was her boyfriend for four years. I’ll never forget it — this slightly haughty, heavily accented babe flouncing round the VIP room of Giorgio Armani asking her stylist if anybody could see her “bush” through her gown. Scroll forward, and the Speedy Gonzales accent is intact, but she’s 10 times more friendly and, with a little weight on her, more glossy and Latinalicious than ever. The star of Desperado and Frida, she’s got that proper, established Hollywood movie-star quality about her, too. Indeed, dressed as she is in YSL, Balenciaga and Gucci (all labels owned by Pinault’s luxury goods conglomerate, PPR), with that high forehead and that wild black hair blow-dried to look like glass, she comes across as a kind of Mexican Catherine Deneuve.

What a shame, one can’t help thinking, she and her billionaire babydaddy (whom she met in Venice at his family’s Palazzo Grassi in 2006, and split with in July), couldn’t make it work. One can just imagine the $3.5m wedding in St Tropez he had planned to throw. The ring he would have given her. Oh my goodness, and the dress. But it was not to be. Despite the fact that they were recently spotted together in Paris in the front row of Balenciaga — and later having tea at the Plaza Athénée hotel with Valentina, a dead ringer for her daddy, playing happily at their feet — it’s supposedly all over. Would that Hayek would elucidate further on this, but she will not. She’s much happier, of course, talking about the real love of her life, who is sleeping in a room upstairs and is obviously soon due for a feed . . .

“I’m like an alcoholic,” she shrugs. “It’s like, I don’t care if I cry, I don’t care if I’m fat, I’m just gonna do it for one more week, one more month, and then, when I see how much good it is doing her, I can’t stop. Eet’s a very powerful thing you know.”

Earth Mother. Movie star. Director. Producer. And now humanitarian. One can see how this “ballbreaker”, as the film mogul Harvey Weinstein once called her, can be a handful. Certainly she was as a little girl growing up in Coatzacoalcos, on the Mexican coast, the daughter of a wealthy, highly indulgent Lebanese businessman and his Spanish opera-singer wife. Spoilt, spoilt, spoilt was how she described her childhood — “If I wanted a tiger, I had a tiger,” she once said. But maybe that wasn’t such a bad grounding, given that one of the first things she was told by a studio head when she went to Hollywood at the age of 25, barely speaking a word of English, was that she could never become a leading lady “because we can’t take the risk of you opening your mouth and people thinking of their maids”.

Seventeen years later, the 5ft 2in Hayek is a powerful force in the industry. Of all those Latina lovelies out there — Eva Mendes, Penelope Cruz, perhaps even Jennifer Lopez — she is the one who has the makings of a proper Hollywood mogul. She heads up her own production company, through which she is an executive producer of Ugly Betty, and has no fewer than four new TV shows on the boil (one of them, piquantly, a reality TV show about weddings). She has also set up another production company, Ventanazul, with MGM, to try to get more Latino films made for the growing Hispanic market. And let’s not forget all the work she’s been doing to support the Unicef campaign to eliminate tetanus in developing countries. She tells of her recent harrowing trip to Sierra Leone. “I was in this room with this 19-year-old mother who came with her baby, five days old and dead. The memory of her trying to force some milk into that dead baby’s mouth . . . I’m telling you, it was really something else.”

The interview is coming to an end and it’s a shame, because I like her very much and we’re having such a good time gassing about bosoms and body image (she’s drinking Guinness to boost her breast milk at the moment, which is putting on the pounds) — and, yes, men. We agree that it can be tricky, finding the Perfect One. “I think it’s important for men to learn to follow someone’s essence,” she says, drawing closer on the sofa to make her point, fingertips pressed to my knee. “So regardless of what happens to the body, they can stay in love. You know, for us women it’s easier to have a relationship with someone just because of that. For a man, they need that plus the other stuff. They need to push further and look at you not just as a human body but as a fellow soul. But so many of them don’t, you know?”

Salma Hayek supports the Pampers and Unicef campaign; unicef.pampers.co.uk

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