What's the story behind your new single, 'Dirty Picture'?
"I wanted something dancey and electro, which is what I'm into at the moment. I worked with [producer] Fraser T. Smith on the backing track and then one day the hook just came to me. I was mumbling stuff to myself and it just came out: 'Can I take a dirty picture?' I thought it sounded really cool, so I wrote the song around that."
Did you write the song from personal experience?
"No, nothing like that! It's not written from a direct experience - it's just a fun song."
The video shoot looked like a lot of fun...
"It was shot in this really cool basement in LA. We wanted it to look like a party scene, but not in a typical club, and it was really good fun. Ke$ha's shots were recorded in London because our schedules were all over the place, and then I shot the rest in LA."
Why did you choose Ke$ha to guest on the track?
"She was completely unknown when we recorded it - she hadn't released a thing - but I'd heard she was an amazing artist and I thought her voice was very unique-sounding, which I like in an artist. I'm really happy for her now she's doing well."
Have you heard her solo version of the track?
"Yeah, she asked me if she could do a version of the song where she sang the first verse and I thought that was a really cool idea. I really like both versions, and it's good that there are these two different versions out there, because fans of me get more of me on mine and Ke$ha fans get more of her on hers."
A little birdie told us Drake's going to appear on the US version - is this true?
"Well... I don't know. I don't yet. I don't like to say anything until everything is confirmed, but we're definitely trying to put a cool feature on there and, as far as I was made aware, Drake loves the song and wants to be on it. People in the background are trying to make it happen."
Were you disappointed with the chart position of your last single, 'No Other One'?
"There are reasons behind that which I won't go into, but it's all good. I'm neither here nor there about it. I'm glad the new single is doing better."
You're one of select group of UK artists to crack America - what's your secret?
"I don't think I have a secret. If you make decent music and make sure a lot of people listen to it, then they'll buy it. It doesn't even have to be about touring. A lot of artists still work on old business models, you know. That's not to say they don't work, but I don't think everyone has to follow them nowadays. Now we have the internet and various other things, people can hear a song in a much quicker period of time, meaning you can get a million downloads in two days, which was impossible before. I was told the other day that something like 80% of my music sales come from downloads, so I would say the internet has definitely helped me break new territories. Also, my songs are generally about topics that are universal - things like love, relationships, happiness and sadness which anyone can relate to."
We hear you've been working on Kylie's album...
"Her team asked me to write for her, and they played me some music in the direction they wanted to go in, so I went off and tried to create music in that vein. I ended up submitting a couple of songs for her, one of which was on hold the last time I heard. I don't know if anything else is going to make the cut on her album yet. And I can't tell you anything about the songs!"
Who else have you been working with recently?
"I've had one recording session so far with McFly and we're trying to sort out some more. We work really well together and the boys seem really excited. We'll definitely be finishing off one song we've done together, and then hopefully doing some more. More recently I've submitted a couple of songs for Rihanna - and some for Justin Bieber and The Saturdays too."
McFly's sound is quite different from your own. Do find that more of a challenge?
"Their new stuff is still quite rocky, and the music I listen to and create is quite diverse compared to what I put out myself. I don't like to pin myself down to a particular genre. I just like to make music that is catchy and fun, whatever genre that may be."
Finally, what's the secret to a creating a hit song?
"Simplicity. Don't make the song complicated. Some of the biggest songs in the world are the most simple, like Whitney Houston's 'I Will Always Love You' - it just says it how people would say it, you know? They don't say, 'I will one day find the words to open the door where I'll find the box of Pandora, where I'll find your heart in which I'll translate that to your energy that will transfer between you and me, which will spell the words L.O.V.E'. You could say that, or you could just say, 'I Will Always Love You'."
'Dirty Picture' is released on May 3.