The Canadian singer has topped the midweek chart with her song 'Call Me Maybe', while Sean Paul continues to hold at number two with 'She Doesn't Mind'.
Nicki Minaj is at three with 'Starships', Gotye is at four with 'Somebody That I Used To Know' and Chris Brown falls to five with 'Turn Up The Music'.
Over on the album chart Nicki Minaj is on course to have her first UK number one album with her latest record Pink Friday: Roman Reloaded.
The rapper's second studio set is currently 9,000 copies ahead of Labrinth's debut album Electronic Earth, which is at two.
Kids' phenomenon Moshi Monsters are at three with Music Rox, Lostprophets are at four with Weapons and Madonna's MDNA slips to five.
> View the current singles top 100 here
Watch the music video for Carly Rae Jepsen's 'Call Me Maybe' below: