High up in a private room on the top floor of Cardiff’s only five-star hotel, the Welsh singer Katherine Jenkins is wearily holding fort. She’s surrounded by female minders as she greets me for this, her 16th interview of the day. On the table there’s a bowl of fresh fruit, two types of bottled water and a jug of fresh orange juice. The view of the late afternoon sunshine streaming across the bay is impressive, but you get the feeling she’s seen better.

Jenkins, like a blonde Cheryl Cole, has her tumbling blonde locks counterpointed with dusky dark eyes and pale glossed lips. She’s wearing nine-inch YSL platform stilettos with black leggings and a Topshop T-shirt. She looks very thin -- and every inch the celeb-about-town.

At 17 she got a scholarship to study at the Royal Academy of Music in London and her first album, Premiere, when she was 23 made her the fastest selling mezzo soprano on record. Her six albums to date have topped the UK classical charts. Yet she makes no bones about letting the world know the importance of image. She takes her beautician, personal trainer, make-up artist and hairdresser with her wherever she goes. “Image is hugely important,” says the star who has just returned from Los Angeles where she made an American network TV Christmas special recording with Italian tenor Andrea Bocelli.

This month sees the launch of Jenkins’s seventh album, Believe. It’s the first with her new American record label Warner Bros, with whom she signed a whopping £5m contract last year. It’s also her first album with David Foster, the influential producer, composer and songwriter who is responsible for the stratospheric recording careers of Barbra Streisand, Celine Dion, Whitney Houston and Michael Buble.

Not bad going for Jenkins, a working-class girl from Neath who has been credited as the creator of the “classical crossover” genre.

While she was a final-year student in 2003, Steve DuBerry, who had produced two of Tina Turner’s No1 hits, persuaded Jenkins to make a demo tape. She recorded Pergolesi’s Stabat Mater and Delibes’ Flower Duet from Lakme, arranged over a dance beat. DuBerry passed it to Universal Classics, who asked her in for an audition -- a terrifying experience she likens to appearing on X Factor -- where she sang a variety of operatic arias, including Rossini’s Una Voce Poco Fa. One hour later they offered her her first contract, a £1m six-album deal. It was the largest record deal in UK classical recording history. She was 22.

Jenkins was told by her then manager Brian Lane that she was “the first of a kind, the most glamorous opera singer in the world”. He told her: “There’s nobody like you, Katherine. You’re a one-off, the first female in the business who is not copying someone else.”

“He thought I didn’t look like an opera singer,” she recalls. “I was wearing a short skirt and singing Ave Maria.” Lane knew nothing about classical music but encouraged her to stay true to it. The “new genre” he’d spotted has been so successful that Jenkins has become a multi-millionaire at the age of 29.

Believe is a gentle, slickly produced collection of standard contemporary songs, including Sarah McLachlan’s 1997 Angel, Till There Was You by The Beatles, a reworking of the 1990s rock band Evanescence’s Bring Me To Life and a title-track duet with Bocelli arranged by Foster himself. Apart, perhaps, from a sung version of the theme from The Godfather, the most surprising entry in the 12-song set is a mesmerising rendition of the Bob Marley classic No Woman No Cry -- with the famous syncopated reggae rythmn replaced by soaring orchestral strings. Jenkins herself describes her version of the seminal song as being “like a lullaby”.

 

Populist

 

There’s no denying that Believe, which launches in the US next spring after the UK tour ends, has a different tone from all her other albums and seems even more populist.

“It is different in its sound and in the choice of songs,” she agrees. “I wanted to make this a more contemporary, more crossover album -- more accessible to people who maybe have not bought a classical album before.”

How would she describe that sound? “It’s epic, it’s Hollywood, it’s filmic. David has this thing -- and he talked about it a lot when we were in the studio -- where if you were watching this live there’s a moment where the audience just wants to get up and applaud. He did it with The Bodyguard, his most famous album [sung by Whitney Houston]. You know the bit: ‘Boom … and I-I-I will always love you-hoo-hoo,’” she sings. “That was such a new thing back then. Believe was about trying to take that and put that into a classical genre and keeping it really exciting, which is why a lot of the pieces start quite soft and intimate and gentle, but then they build these really operatic endings.

“I’ve always wanted to work with David. He has heard the best voices in the world. I feel I’ve been working with a genius.”

Did she feel it was time for a change of direction? “It was definitely the right time,” she answers. “This is my seventh album and not that I would ever take it for granted, but you do become used to the process.

“Now with a new record company, new producer, and a new aim of breaking into America, I’m totally re-energised. It’s great to be going into a place where nobody knows me and to have to start all over again.”

For her American debut, Jenkins has got herself on to the books of one Liz Rosenberg, the US public relations giant who has represented Madonna throughout her career. As it happens, Madonna has been Jenkins’s idol since childhood. Material Girl was the first song she ever bought, though more for the video than for the music or the voice. “I saw her on the telly, not on the radio, and I just said, ‘Wow, what is all this about?’. I thought it was the most glamorous video I’d ever seen,” she recalls. “Madonna, with her blonde hair, diamonds and pink dress, was just like my idol, Marilyn Monroe.”

So how did she manage to bag Rosenberg, who has also represented Cher, k.d. lang, Liza Minnelli and Stevie Nicks? “It was the record company who suggested her, though she is so well established that she only takes on a few acts that she wants to work with,” says Jenkins. “I met with her and we just totally clicked. I feel like she has been my friend for my entire life. She’s the best fun and she very kindly said she’d like to work with me too.”

She hesitates when I suggest a change of image might be on the cards. “I can’t really say,” she says, glancing over at her PR manager. “But with Liz it’s all really about the buzz she can create. She’ll be talking to the press and TV shows, setting up all my interviews.”

I’m exhausted just listening to her. Seven albums in six years, plus all the publicity. Doesn’t she ever feel the same? “I’m so lucky that I’m getting to do a job like this, and doing the publicity is a major part of it,” she says. “Being realistic, without that I wouldn’t be doing the concert tours and making the albums. Besides, I’ve always enjoyed chatting to people.”

 

Going live

 

Jenkins turns 30 next June. She has stated her intention of doing live opera by the time she hits her 30s and when her voice is ready. But it seems her hugely successful crossover career, which fulfils her youthful ambition of wanting her voice “to reach millions and touch people everywhere”, is taking her off-plan. Student productions apart, she has yet to perform in a live opera as a professional singer without the use of a microphone. She has, however, got a BA in performance from the Royal Academy.

“I still hope that I will do opera,” she says, “but the crossover thing is happening and I’m really really enjoying that. But I think I might do something like Carmen in the next year or so. For now, I need to focus on the album.”

Bubbly and talkative, she seems content to be known as a classical crossover singer whose life revolves around live big-venue concerts, CD launches, touring and publicity.

“A crossover singer is somebody who can span both genres, who has had a classical training but who can also be flexible and perform in Live Aid or bigger venues such as football or rugby stadia,” she says. She herself has sung at Westminster Cathedral, the Welsh national rugby stadium, on the Live 8 stage in Berlin, in Trafalgar Square on VE Day. Who would she rather compare herself to between operatic soprano Lesley Garrett and musical singer Sarah Brightman? “They’re both very different. I’d like to be somewhere in the middle. I’d like to do something between Josh Groban and Andrea Bocelli.”

Meanwhile, she is now friends with the world-famous opera singer Placido Domingo, one of the Three Tenors and now general director of the Los Angeles Opera company. Earlier this year he invited her to be his guest at a performance of Verdi’s Othello in LA, and has also offered to advise her on new repertoire and to coach her on some technical points. While in LA this summer, she had a lesson with him.

“I feel like I’ve learned so much in just one 15-minute session with Placido,” she says. “It was just him and me and the piano. He talked about the technique he’s learned and helped me with my breathing and support. He was teaching me how to use my stomach muscles more and to take fewer breaths, to make a more supported sound, whether it’s smoother or louder.” Voice projection is, of course, one of the prerequisites for singing opera. Does she think he’s trying to steer her towards an operatic career? “Yes. He’s giving me the confidence to try it. Placido has always said, ‘I think that with the right help you could be really good at this.’ To hear somebody so well respected telling you something like that is amazing. I hope to get more lessons from him when I’m back in LA. Opera is the thing that really moves me. I’d like to see if I can do it.”

She does not call herself an opera singer, and blames the ignorance of the press for giving her that moniker. “I’ve never called myself an opera singer. When I do opera I will call myself an opera singer,” she says firmly.

She believes it would be impossible to perform well in opera without having experienced emotional trauma. The most important thing about singing, she says, is the meaning and the message. “You have to have experienced love and loss. How else could you do it? I think it would be impossible.” Maria Callas is another of her idols. “She had such a tragic life and she was first to bring real emotion into opera. She was such an amazing singer. That’s someone I’d aspire to for sure.”

Jenkins lost her beloved father Selwyn to cancer when she was 15, and has recorded a version of Pie Jesu in his memory. The loss of her Glasgow-born maternal grandmother Nanna soon afterwards was another blow.

“I’m drawn more to emotional songs and I think people do respond to songs that are sadder because everyone has a bit of angst in them, and they project their own emotions and experiences on to songs like that.”

She lives with the Welsh TV presenter Gethin Jones, her boyfriend of two years, in her Victorian North London home, which has a “huge kitchen that is the hub of the house” and a large garden which is being redesigned. They’ll hire a gardener to look after it because they don’t have the time to do it themselves, although they love cooking together, and she loves coming back to the house after time away. She’s reluctant to discuss her relationship with Jones further, other than to say “we’re very happy” with a nervous giggle. “We’ve made a pact not to talk about us,” she says. Jones is an avid rugby fan as well as a violinist and piano player and their circle of friends in London include the Scottish rugby player Kenny Logan and his wife Gabby.

She first met Jones in 2007 when he and Logan were contestants on BBC’s Strictly Come Dancing, where she performed Time To Say Goodbye with Bocelli.

What does love feel like, then? “Aha, good try,” she laughs. “I don’t talk about me and Gethin because there’s such a lot of interest in us. We’re trying to keep home life and work separate. I want people to be interested in my music rather than my relationship.” They rarely attend events together and have to “be careful” when they do venture out together. She is looking forward to spending their first free Sunday together for months.

 

Coping with pressure

 

Emotional contentment or otherwise does not affect her singing, she says. “When I’m on stage it doesn’t matter if I’ve had the worst day ever because I’m back in that bubble. I look forward to going on because nothing’s going to interrupt you or your music. It’s harder to sing songs that have a really emotional meaning when you’re sad, but you just have to detach yourself. At the Bobby Robson memorial concert recently [for the former England manager at Durham Cathedral] I sang, went back to my seat and had a little bit of a cry about it. But if you even let it enter your head it goes to your voice.”

Nevertheless, the physical and psychological pressures of her celebrity lifestyle are mounting. The need to stay fit and well is constant. “Health is a big issue when your livelihood is performance. It’s constant and staying well and keeping up with it all, especially now, can be insane,” she admits. “I mean, getting five hours’ sleep a night, travelling in planes, all this kind of stuff. Looking after my voice is constant because it’s pretty manic. But if I haven’t looked after my voice I have to cancel a concert and then you’re letting all those people down. I think I’ve cancelled once and I felt terrible about it.

“I try to live as healthy a life as I can. I don’t have much alcohol because that dehydrates your voice. I also take vitamin C, zinc, Echinacea and try to stay away from bugs if I can.

“I’m motivated by it because I love it, but there are times when you’re really, really tired. Not being in touch with my mum Susan and my younger sister Laura as often is difficult and you’re constantly trying to find ways of keeping in touch through Skype and Twitter. At the same time, trying to keep the line between work and private life and having to protect that can be wearing.” When she was student at the Royal Academy, Jenkins developed an eating disorder following a stint on the Atkins diet. She also famously, as a student before she became a recording artist, dabbled in cocaine and ecstasy as well as cannabis -- one of her biggest regrets, she says, although she does concede her sensational confession last year to a UK tabloid newspaper did help muddy her squeaky-clean image. She’s now a pescovegetarian -- a vegetarian who eats fish. Avoiding dairy products helps reduce the production of catarrh and mucus, which has a negative effect on the voice.

Does she foresee a time when she might consider taking a sabbatical to relax and recharge her batteries? “Yes,” she replies swiftly. “But probably only when I’m really settled and having babies. I’ve always wanted lots of children.”

Throughout our interview, Jenkins repeats the phrase “before all this happened to me” several times while discussing her career. She once said her early ambition was to become a music teacher, join the chorus of an operatic company and hopefully work her way up from there to becoming a soloist. But instead she’s ended up living a fairytale of fame, fortune -- and designer dresses.

“I am living the dream,” she says. “But deep down I’m just like everyone else.”

Later, while I’m waiting for my cab, I spot the People’s Diva sweep, stoney-faced, through the lobby and out of the hotel. The slick silver Merc that’s waiting for her knows where it’s going: back to London and the home in which she’s left her loving heart.

Believe is released in the UK on Monday. Katherine Jenkins’s UK tour reaches the Clyde Auditorium, Glasgow, on Thursday, March 4, 2010. For tickets, call 0844 499 9990 or buy online at www.gigsandtours.com and www.ticketmaster.co.uk.