New York dance star Lady GaGa has topped the UK singles charts with Just Dance, knocking Alexandra Burke off the number one spot.
The 20-year-old, real name Joanne Stefani Germanotta, had entered the chart at number three last week.
A Grammy nominee for Just Dance, she also finished sixth in the BBC's Sound of 2009 list.
Broken Strings, a duet between James Morrison and Nelly Furtado, climbed three places to number two, while X Factor winner Burke's Hallelujah dropped to number three.
The top ten singles in the UK are:
1 Lady GaGa: Just Dance
2 James Morrison feat. Nelly Furtado: Broken Strings
3 Alexandra Burke: Hallelujah
4 Leona Lewis: Run
5 Kings Of Leon: Use Somebody
6 The Saturdays: Issues
7 Beyonce: If I Were A Boy
8 Beyonce: Single Ladies (Put A Ring On It)
9 Katy Perry: Hot N Cold
10 Kevin Rudolf feat Lil Wayne: Let It Rock
The top ten albums in the UK are: (last week's position)
1 Kings of Leon: Only By The Night
2 Take That: The Circus
3 Duffy: Rockferry
4 Leona Lewis: Spirit
5 The Killers: Day & Age
6 The Script: The Script
7 James Morrison: Songs For You, Truths For Me
8 MGMT: Oracular Spectacular
9 Ting Tings: We Started Nothing
10 Beyonce: I Am Sasha Fierce