The 'California Gurls' singer and her fiance Russell Brand have made a pact not to speak about their romance once the wedding has taken place.
She said in an interview on 2Day FM's Kyle and Jackie O Show: "People have all these ideas about my relationship and my wedding and there is so much speculation. I'm not a traditional type of person in general but after we get married we've decided we're not going to talk about the relationship."
Katy - who has refused to reveal the date of the impending nuptials - also claims she and Russell won't make an announcement to say the ceremony has taken place.
She said: "This whole process is exciting but once you're married it's supposed to be for life so when you hear us stop talking about it we'll be married."
The 25-year-old singer - who has admitted making up stories about the wedding so people will be surprised when the big day finally arrives - insists she is the only person who knows all the details.
She explained: "Let people think what they want to think. Only I know exactly what is going on and I want to keep it that way."
However, she is in the dark about her bachelorette party, which is being arranged by close friend Rihanna, although she has some ideas about how it will turn out.
She said: "I know it's going to be my one last hurrah and I'm probably going I'm going to end up s**tfaced in an alley wearing a penis hat. It'll be horrible so brace yourselves people!"
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