Usher holds B.o.B., Perry off Oz top spot

Usher has fended off stiff competition from B.o.B. and Katy Perry to remain atop the ARIA singles chart.

His hit 'OMG' - current No.1 in the US, and a recent chart-topper in the UK and Ireland too - notches up a fifth week at the summit.

B.o.B. holds steady at two with 'Airplanes', a collaboration with Paramore singer Hayley Williams, while Perry rebounds to three with 'California Gurls'.

Meanwhile, Jason Derulo climbs from seven to a new peak of five with 'Ridin' Solo'.

The Glee cast leap from 15 to 8 with their version of 'Jessie's Girl' - originally an Aussie chart-topper for Rick Springfield in 1981 - while David Guetta climbs from 16 to 9 with 'Gettin' Over You', the current UK No.1 single.

The top ten singles in full (click where possible for our reviews):

1. (1) Usher ft. will.i.am: 'OMG'
2. (2) B.o.B. ft. Hayley Williams: 'Airplanes'
3. (5) Katy Perry ft. Snoop Dogg: 'California Gurls'
4. (4) Yolanda Be Cool & DCup: 'We Speak No Americano'
5. (7) Jason Derulo: 'Ridin' Solo'
6. (3) Ke$ha: 'Your Love Is My Drug'
7. (6) Taio Cruz: 'Break Your Heart'
8. (15) 'Glee' Cast: 'Jessie's Girl'
9. (16) David Guetta & Chris Willis ft. Fergie & LMFAO: 'Gettin' Over You'
10. (17) Chiddy Bang: 'Opposite Of Adults'