The pop star's new song is all about finding hope after a dark period

She may be very pregnant at the moment, but that's not stopping Katy Perry from ploughing ahead with her new album.

The 'Roar' singer has announced details of the follow-up to 'Witness'.

'Smile' will be released on August 14th and she also revealed details of the artwork.

"I wrote the title track from the album when I was coming through one of the darkest periods of my life and had lost my smile," she revealed on social media. "This whole album is my journey towards the light – with stories of resilience, hope, and love."

The lyrics of the song include 'Had a piece of humble pie / That ego-check saved my life' and 'Going through motions felt so fake / Not myself, not my best / Felt like I failed the test.'

Perry also recently revealed that she had become "very upset and clinically depressed" after the release of her last album 'Witness', which underperformed sales-wise in relation to her previous material.

"I became very insecure and had to go on a journey, both emotionally, spiritually, and psychologically to understand why I relied so much on validation," she said in a recent interview. "I had to realise that everything related to my career isn’t all of what life is, it’s just a part of who I am."

Perry is expecting her first child with fiance Orlando Bloom, which they had previously announced is a girl.

Hear 'Smile' below: