Katy Perry has revealed she is not pregnant with fiancée Russell Brand's baby.

The singer triggered speculation last week when she joked that she was “prego-ed” on Twitter.

Katy and Russell, who got engaged over New Year, were also spotted looking at items in a children's shop in London on Sunday.

But in an update on Twitter, Katy said she couldn't be pregnant because she was on her period.

Katy Perry and Russell Brand both had seperate sessions at the gym yesterday.

“ur gonna make me cry, maybe that's my period tho. THAT'S RIGHT I'M BLEEDING,” she wrote.

“Face. Better luck next month peepz.”

The singer's denial came just hours after she was spotted leaving a gym in Los Angeles wearing a pussycat t-shirt and black leggings.

Russell was also spotted going for his own workout yesterday sporting the team colours of football team West Ham.

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