Number one single for Lady GaGa

Lady GaGa, by Lady GaGa, has been nominated for a Grammy

Hip New York singer Lady GaGa has hit the top spot in the UK with her single Just Dance, ending X Factor Alexandra Burke's three-week reign.

The single, featuring Colby O'Donis, had been a new entry in last week's chart at number three.

James Morrison and Nelly Furtado's duet Broken Strings rose from five to two while Burke's Hallelujah is this week's number three.

In the album chart, Kings of Leon took the number one slot from Take That.

The bands swapped places with Only By The Night beating The Circus into second place.

Electro-pop princess Lady GaGa, 20, came sixth in the BBC's Sound of 2009 list.

The singer, real name Joanne Stefani Germanotta, has been nominated for a Grammy for best dance recording for Just Dance.

The song is her first release in the UK.

Also in the singles chart, Leona Lewis' Run dropped two places to number four while the Kings of Leon rose one place to five with Use Somebody.

Girl band the Saturdays leapt from number 27 to number six with their song Issues.

And singer Beyonce holds both the number seven and number eight positions in the top 10.

Her song If I Were A Boy dropped three places to number seven while Single Ladies (Put A Ring On It) rose from number 14 to number eight.