Katy Perry is planning to create a special aroma for her 2011 European tour which starts in Lisbon, Portugal on February 20 and runs until April.

Perry said: "It's going to engage all the senses, so we're looking into alternative stuff like smell. We're talking to a couple of companies at the moment about creating an aroma for the performance."

Perry's UK tour dates have all sold out. 

Watch Katy Perry perform 'Firework' on the Top of the Pops' Christmas Day Special 2010, below: