Katy Perry's mother spotted pregnancy surprise

Katy Perry's mother spoiled the elaborate pregnancy reveal she had planned for her family.

The 35-year-old pop star thrilled her fans this week when she announced she is expecting her first child with her fiancé Orlando Bloom by dropping the music video for 'Never Worn White', which at the end showed her cradling her baby bump.

Katy then confirmed the news in a subsequent Instagram Live video, admitting it is "probably the longest secret" she has "ever had to keep".

The 'California Gurls' singer also organised a fun way to break the news to her family that she was having a baby - by having it printed on a wine label.

But her mother Mary Hudson foiled the plan when she spotted the wine bottle on an impromptu visit to her daughter's house.

Speaking about the happy news on Mikey Piff's SiriusXM radio show, Katy said: "She just came over and was looking at my wine, which she never does, and she's like, 'What is this?' And that's how it happened. And I was like, 'Well, you ruined the surprise,' but I guess mums have intuition unlike any other, right?"

Even though she is going to became a parent, Katy has no plans to ease up on her music career and intends to join "the force of working moms out there".

She said: "I'm joining the force of working moms out there. And that is a very strong force! And I love what I do and it doesn't feel like work and it brings me so much joy, so I just want to continue that state of joy."

The baby is the first for Katy and Orlando, although the 43-year-old actor does have a nine-year-old son, Flynn, with his ex-wife Miranda Kerr.