LONDON (Reuters) - U.S. producer will.i.am's collaboration with Britney Spears topped the British pop charts on Sunday as David Bowie notched up his first top 10 single in two decades with his surprise new release.

Launched without warning on Bowie's 66th birthday, the single "Where Are We Now?" caused widespread media interest, and charted in sixth place despite only having been available for five days.

It was his first new song in almost a decade and produced his best chart performance since 1986, when he reached number two with "Absolute Beginners", the Official Charts Company said.

Topping the chart was "Scream and Shout" by will.i.am, featuring Britney Spears, giving her a first British number one since 2004.

U.S. country-pop star Taylor Swift's "I Knew You Were Trouble" moved up to second, with James Arthur, winner of the British version of the "X Factor" TV talent show last year, dropping from first to third with "Impossible".

In the album chart, singer Emeli Sandé returned to number one with "Our Version of Events", which has now spent 48 consecutive weeks in the Top 10.

Last week's chart-topper "18 Months" by Scottish producer and singer Calvin Harris dropped to second place, and English singer Jake Bugg rose a place to third with his eponymous album.

R&B star Rihanna climbed three to fourth with "Unapologetic". The only new entry in the top 10 was the soundtrack from the Oscar-nominated film musical "Les Miserables", which debuted in fifth.