Perry had asked Rihanna to help her organise her Bachelorette party before her wedding.
'I have to come up with something cool because she is getting married in India so I'm like, 'OK, now what do I do to match that?'
'That's at the end of the year so we've got some time to plan,' The Sun quoted Rihanna, 22, as telling US radio DJ Ryan Seacrest.
The couple's nuptials are set to be a star-studded event -- with Brand's close pals, including David Walliams, Jonathan Ross and Noel Gallagher.
Perry's guest list is expected to include pop star Taylor Swift.
Photographs: Danny Moloshok/ Reuters
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