Pop superstars Beyonce and Shakira have beaten British rockers Arctic Monkeys to the top of the UK singles charts with their duet, Beautiful Liar. The Arctic Monkeys song Brainstorm is at number two, while last week's chart-topper Timbaland is in third position with Give It To Me featuring Nelly Furtado and Justin Timberlake. Avril Lavigne's Girlfriend slips one place to number four, while Mark Ronson's mish-mash single Stop Me falls from number two to five. Meanwhile, Lavigne's new album The Best Damn Thing has debuted at the top of the UK album charts, with Ronson's Version also a new entry at number two.