Rumours that the X Factor mogul is expecting his first child with New York socialite Lauren Silverman began earlier this summer, but last night at the world premiere of One Direction's This Is Us movie marked the first time Simon confirmed the news.
He told BBC: "Things are changing in my life right now for the better. I'm proud to be a dad. It's something I haven't thought of before and now I feel good about it."
Simon made a surprise appearance at London's Leicester Square to support Niall Horan, Zayn Malik, Louis Tomlinson, Liam Payne and Harry Styles at the screening of their first-ever feature-length movie.
The 53-year-old was accompanied by ex-girlfriends-turned-close-friends Sinitta and Mezhgan Hussainy, but there was no sign of Lauren.
Simon's willingness to talk about his child was a contrast to his tight-lipped stance at a press conference at the start of August, where he jokingly said he hadn't read the newspapers and appeared to be "missing something".
When pressed, he replied: "Unfortunately, I have to keep this private for the moment. It's just one of those things, but thank you anyway."
Simon had said in the past that while he was fond of children, fatherhood might not be for him. He said in 2009: "God, no. I couldn't have children. If I had them here drawing on the walls I'd go nuts."
While chatting at the premiere last night, Simon joked about impending fatherhood by saying he felt like a "father" when he looked back on One Direction's massive success.
He was a judge on X Factor when Niall, Zayn, Louis, Liam and Harry auditioned as soloists but were put together as a band, and they're now signed to his Syco Records.
Watch a trailer for This Is Us below:
More celebrities expecting babies this year:
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