Louis - who briefly managed Girls Aloud after they won 'Popstars: The Rivals' - suggested the only reason Cheryl was successful was because of her marriage to footballer Ashley Cole.
Louis Walsh. Saucer of milk not pictured
"[Nadine] is the best singer. By a mile," he told The Gaurdian. "But she didn't marry a footballer. If she'd married a footballer she'd have been a big star."
Louis and Tulisa
"She works hard; she's honest," he said. "I did say she's a chav in a tracksuit, but she's a good chav in a good tracksuit.
"She's a lovely girl," he added. "We bonded from day one. I was dreading meeting her. I thought she was going to be a right little knacker. You know, a real toughie."
The girls knocked back the champers on Saturday night at the Light Bar in London's St Martins Lane Hotel.
Girls Aloud celebrate at London's Light Bar
And the party really kicked off when the girls found out their latest single, 'Something New', had shot to number one on the iTunes chart. They celebrated by hitting the dancefloor and dancing to the tune before joining in on Stevie Wonder’s Happy Birthday to Kimberley and Sarah.
Despite leaving in the early hours, all five girls made it to Wembley last night to perform on 'Strictly Come Dancing'.
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