Following a high-profile appearance with rumoured fiancée Mezhgan Hussainy at Elton John's Oscars party, the music mogul appeared to confirm the couple's engagement on The Tonight Show with Jay Leno this week.
The American Idol judge, 50, faced a number of questions from his host about the numerous reports he will wed the makeup artist this summer.
Asked to confirm the news, Simon paused, before carefully responding: "Are they (reports) true? Well, I do have somebody in my life now, Jay, yes. And I kinda made a decision this year to make somebody happy."
The private Brighton-born millionaire went on to admit the questioning was making him blush, before his persistent interviewer asked: "Where did you, or may have, gotten engaged?"
"I find this very uncomfortable. I was asleep, I think. No, look, I bought her the ring in London," he said.
The ring he was referring to is the huge diamond sparkler Mezhgan has been seen wearing on her left hand since she was reportedly given it on Valentine's Day.
Eagle-eyed Jay then spotted the 36-year-old brunette in the audience and called her to join Simon on stage, where the two shared a kiss.
Despite many sources saying Simon and Mezhgan will marry before autumn, Simon would only say he wanted to wed "in the next ten years."
He also talked about the possibility of children, adding: "I'm kind of torn because I'm too old to have kids, but then again I think it would be important to have lots of me's around in the future."
Simon's appearance on the US chat show follows an interview with his Britain's Got Talent co-judge, and friend, Piers Morgan, who, coincidentally, is also set to marry this summer.
On the presenter's Life Stories show, the music executive said of his Afghanistan-born love: "She's the one."