Covering love songs such as Mona Lisa by Nat King Cole, I Can't Help Falling in Love With You by Elvis Presley and Your Song by Elton John, Connick Jnr has hit the Top 10 of the Billboard album chart in the US and topped its jazz chart.

Yet it wasn't an easy transition for a singer who'd always controlled his own sound and recordings right down to the mixing. For a start, Davis, the founder of Arista Records and who helped catapult Whitney Houston and Alicia Keys to global fame, was calling the tunes. He picked some songs for the album, and Connick Jnr the others. A few they disagreed over.

'Normally, I would pick the first songs that came into my head and sing them,' says Connick Jnr, sat on a sofa in a suite at the Landmark Mandarin Oriental, the day after he showcased seven of the album's tracks to a selected audience in the hotel's MO Bar. 'This was a much more scientific approach. Clive suggested I do a CD where my vocals were really featured, where it wasn't about the arrangements or the piano or the orchestration or songwriting,' recalls Connick Jnr, who has admitted his complex musical constructions have at times overshadowed his own vocals. 'It was about me singing these songs that everybody knew. And I said, 'Yeah, that sounds cool'.'

While Connick Jnr arranged the songs to stamp his own style on them, Davis was hands on, asking him to rerecord tracks to meet his exacting demands. The singer reportedly had to hire a band in New York to add grandiosity to a track he'd already recorded with a different band in Los Angeles.

'It was totally different. We banged heads a little bit,' says Connick Jnr. 'I think it was mainly a matter of not understanding each other's language. I mean, I'm speaking from a completely musical point of view. He's speaking from a much more personal, emotional point of view.

'It was like when I wrote an arrangement for Mona Lisa, he would hear the arrangement and he'd say 'at one minute and 37 seconds I think there should be more strings there', or, 'at two minutes and seven seconds there should be a saxophone solo or more piano', things like that. I've never had that dialogue with anyone before. He would sometimes have difficulty expressing what the alternative was.

'But as we got to know each other we realised we both had the same CD in mind. Once we got on the same page with the language, it was great and in the process I made a really good friend.'

At Sony's suggestion, he did a duet with Carla Bruni, the former model and current first lady of France. The French- and Italian-language versions of And I Love Her are designed to create a stir in Europe and Connick Jnr is full of praise for her talent. He says he's happy with the outcome and doesn't feel he has sacrificed any of his artistic integrity by going for the mainstream audience.

'I gotta go to bed at night with my own conscience. I gotta be happy about what I do,' he says. 'Clive's job is to sell records. My job is to make music. If this record sells 10 million then great. But if it doesn't, that's OK too. I have to be happy with my own musical decisions.'

On stage at MO Bar - where he played piano, trumpet and sang in a display of his considerable talents - Connick Jnr spoke of his awe at recording Mona Lisa on the same piano, in the same room of the same studio that Cole had made the song. 'I've recorded at least 10 records there. It's just a great sounding room,' he says.

Connick Jnr, whose albums are normally more jazzy and less pop-oriented, had resisted tackling such classic songs before, yet he says he wasn't intimidated by finally taking on the challenge.

'I think people understand it's a testament,' he says. 'The great thing about the Beatles' song And I Love Her is that anybody can sing it. It's just a great piece of music. I didn't really think about the originals too much. I know Nat Cole's version of Mona Lisa, Your Song by Elton John. You're not gonna do it better than them. So if you treat the song as an objective piece of music and then start the interpretive process from there, it's gonna be different.'

Now living in Connecticut with his wife, actress and former model Jill Goodacre, and three daughters, the city of his birth remains dear in his heart. After Hurricane Katrina devastated the Big Easy in 2005, he teamed up with his long-time collaborators, jazz musicians Branford and Wynton Marsalis, and Habitat for Humanity to start the Musicians' Village project.

Through fund-raising and awareness, they have built 80 homes for displaced musicians and are about to construct the Ellis Marsalis Centre for Music for musicians to teach, perform and record.

'The city was a wreck, man. It was really bad,' recalls Connick Jnr, who says New Orleans was in danger of losing its musical heritage. 'It was bad even before the storm. Traditional music was on the way out, which was tragic and panic inducing for people like me who are here because of that.

'The village is an actual physical place where we know the music will continue to be passed on from generation to generation.'

Connick Jnr attributes his success to the musical influences of his childhood. His parents, who once owned a record store, encouraged him when he began performing at the age of three.

'It was a part of the culture. Everywhere you go there was music,' he says. 'It was like being in Willy Wonka's chocolate factory.'

After moving to New York as a young man, he quickly struck the big time, gaining the world's attention in 1989 with It Had to Be You from the soundtrack of When Harry Met Sally. When he did turn his hand to acting he became a movie star almost overnight, debuting at 22 in Memphis Belle, then starring opposite Jodie Foster in Little Man Tate, Will Smith in Independence Day, and Sandra Bullock in Hope Floats. In all, he has appeared in at least a dozen movies, most recently opposite Ren?e Zellweger in the romantic comedy New in Town. And he has won an Emmy. But it's his musical ability that has burned brightest.

Not afraid to stand up for his beliefs, Connick Jnr recently cancelled an appearance at a Sydney shopping mall after becoming embroiled in a dispute over the performance of a group of 'blackface' performers who impersonated the Jackson Five on Australian TV variety show, Hey Hey It's Saturday.

'It was very hot. It was a subject that was very, very controversial. So we just decided to take a couple of days off. I wasn't worried about physical harm,' he says.

Connick Jnr scored the act a zero and his open disgust at the skit for reviving racist 'minstrel' acts of the past bothered some viewers who saw it as harmless fun.

'I'm pleased with the way I handled the situation,' he says. 'I handled it in exactly the manner I thought was appropriate.'

Connick Jnr also issued a statement on his website this week asserting that while he had a sense of humour, the joke was offensive where he came from.

A devout Catholic, he still has one major ambition to achieve - performing for the Pope. Connick Jnr was asked to sing for the pontiff last year, but it didn't happen.

'I found out later that that opportunity was offered to get me to sing at this big Mass, but the Pope wasn't even there when I sang, which I was really bummed out about because I'd like to have done that,' he says.

'I wrote a big orchestral piece for him. He wasn't even at the stadium when I did it, so I was real disappointed about that.'

If Your Songs proves as big as Davis hopes, the Pope could miss out. Connick Jnr may have a busier schedule next time he's asked.

Your Songs is out now