The Australian star's global hit 'Somebody That I Used To Know' retains the number one position on the midweek chart, while Alexandra Burke's 'Elephant' trails 7,000 copies behind at two.
Nicki Minaj remains at three with 'Starships', Emeli Sandé falls two places to four with 'Next To Me' and Flo Rida completes the top five with 'Wild Ones'.
Taio Cruz leaps 15 places to 19 with new single 'Hangover', Jason Mraz enters at number 23 with 'I Won't Give Up' and Azealia Banks make her UK chart debut at number 27 with '212'.
Further down the chart Coldplay climb five places with 'Charlie Brown' up to number 33, while LMFAO's new single 'Sorry For Party Rocking' is at 36.
Over on the album chart The Military Wives take hold of the top spot with their debut album In My Dreams, which debuted at number two on Sunday's listings.
BBC Sound of 2012 winner Michael Kiwanuka reside at number two with his debut collection Home Again, while Emeli Sandé's Our Version Of Events completes the Top 3.
> View the current singles top 100 here
Watch the music video for Alexandra Burke's 'Elephant' below: