The singer/songwriter's Kimbra collaboration has now sold a total of more than 558,000 copies since its release, making it the first track in 2012 to break the half-million barrier.
Emeli Sandé regains the runner-up spot after climbing one with 'Next To Me', while Nicki Minaj achieves her best UK chart position yet with 'Starships', up to three from last week's five.
Meanwhile, girl band StooShe achieve today's highest new entry at five with their Travie McCoy team-up 'Love Me'.
Also debuting is 'Bright Lights' by Tinchy Stryder and Pixie Lott at seven, as well as the first single from X Factor runner-up Marcus Collins, 'Seven Nation Army', at nine.
Nicki Minaj acheieves a second entry in the Top 10 with her David Guetta collaboration 'Turn Me On', up one from 11, while Kelly Clarkson is back in the double digits after falling four to 12 with 'Stronger'.
Chalking up a greater loss this week are Dappy and Brian May, who crash from two to 13 with 'Rockstar', and Ed Sheeran, down five to 14 with 'Drunk'.
'Mirror' by Lil Wayne and Bruno Mars advances to 17 from 20, Jay-Z and Kanye West climb a mighty nine places to 18 with 'Ni**as In Paris' and Chiddy Bang's 'Ray Charles' closes the upper half of the chart after falling seven from last week's 13.
Source: Official Charts Company
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