Camila Cabello almost gave up trying to write 'Havana'.

The 21-year-old star has topped the charts around the world with her catchy single, but Camila has admitted she nearly walked away from the song at one stage because she found it so tough to write.

She shared: ''It's crazy, because that was definitely by far the hardest song to write on the album.

''It got to the point where I remember my mum and my manager were like, 'Don't even work on 'Havana' any more because we don't even have a song'. For my birthday I went to the studio with Pharrell.

''We were on the couch and he started singing something. And then I started singing something and we figured out the words in, like, 20 minutes.''

And Camila is thrilled that the track ''connected with people'' around the world.

She told The Dan Wootton Interview podcast: ''It's actually incredible that it connected with people, especially knowing how much I was pulling my hair out with this song.''

Meanwhile, Camila has admitted that her experience with Fifth Harmony was ''super intense''.

The chart-topping singer - who quit the girl group in December 2016 - confessed she wasn't prepared to handle the fame and attention that came her way after she joined the band as a teenager.

She said: ''It was super intense. What we have in common with the One Direction boys is that we all started super young.

''We were all really young and we had no experience in the music industry.

''So it's all these new experiences that a lot of us weren't even mentally trained for. Because a lot of kids are groomed from when they're three, like, taking singing lessons and acting lessons and doing auditions.

''When you're 15 and you're singing in your bedroom, then all of a sudden your stage is the entire world, it can be a lot to handle.''