Julia Volkova, 16, and Lena Katina, 17, took the top spot from the Fame Academy winner with All The Things She Said.
But it hasn't all been plain sailing to the top for the gals.
Their video has caused some people to get angry because it shows them kissing in the rain behind bars, dressed in school uniforms.
Some think it's too naughty and the girls go "too far".
TV presenters Richard Madely and Judy Finnegan have even asked people to boycott the single.
The girls say they are going out together.
But there have been rumours that this is just make-believe for their image and that they actually have boyfriends back home in Russia.
Kelly's two
Meanwhile, Destiny's Child Kelly Rowland has nicked the number two spot with Stole.
She pushed fellow band mate Beyonce and Jay-Z down to number four.
New entries to the chart included Ozzy Osbourne's wild child Kelly whose single Shut Up reached number 12.
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