The 53-year-old music mogul and US X Factor judge, took to Twitter earlier today to set the record straight, saying that he couldn't attend because of scheduled filming.
Cheryl, who turned 30 yesterday, celebrated reaching the milestone with boyfriend Tre Holloway and some of her Girls Aloud bandmates, Nicola Roberts and Kimberley Walsh at nightclub Hakkasan.
Taking to the social networking site, Simon assured fans that the two are still 'close friends. He said: 'I didn't snub Cheryl's party. I just couldn't go because of my filming dates. We are close friends again and I adore her.'
And I didn't snub Cheryl's party. I just couldn't go because of my filming dates. We are close friends again and I adore her.— Simon Cowell (@SimonCowell) July 1, 2013
Simon and Cheryl had a fall out in 2011 after Cheryl got axed on the US X Factor after just three weeks on the show.
Her public dismissal tainted the pair's friendship, but this year they slowly started to settle their differences, and judging by Simon's declaration, they are now back to being the close friends they once were.
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Copyright: Twitter Kim Kardashian