Katy Perry announced the name of her upcoming album "Prism" on the side of a gold lorry which travelled through the streets of Los Angeles. The gold truck was emblazoned with black capital letters which read "Katy Perry. Prism. 10.22.2013". The lorry appeared on Monday morning in L.A. and has been photographed since, Perry has promised the truck will be dropping in on other US cities, but its schedule has not been announced. 

Katy Perry
Katy Perry at the premiere of The Smurfs 2 in L.A.

The stunt was pulled in Los Angeles but Perry has promised the lorry will be visiting more cities. She's also promised fans, via Twitter, that if they can find the Prism truck she will re-tweet them. Her tweet yesterday (30th July) reads "Find the #Prism semi, take a picture and I'll RT you. Don't worry, Los Angeles is just the first stop on the map."

A number of Perry's fans are disappointed the lorry's travels will only be limited to the USA and many have simply drawn pictures of the lorry in the hope of attracting Perry's attention. This appears to have worked as one of Perry's followers 'A Little Spark' had her post retweeted "for effort".

The stunt comes days after Perry appeared at the premiere of Smurfs 2 for which she provides the voice of Smurfette.  It has recently been announced, according to US Weekly, that Perry has collaborated with Britney Spears on a special track for the film.

Hear Katy Perry in Smurfs 2 which is out in US cinemas now and UK cinemas today (31st July).

Britney Spears
Britney Spears at the premiere of The Smurfs 2.

Katy Perry
Katy Perry at the premiere of The Smurfs 2.