The business tycoon got down on one knee during a romantic trip to Monte Carlo, and popped the question with an incredible £40,000 diamond ring.
The 67-year-old announced the news with a short Twitter post, writing: "It is true @wnigora_nigora & I are now officially engaged." Nigora also took to Twitter to thanks fans for all of their well-wishes following the good news.
The couple got engaged in Monte Carlo
The couple met at Harley Street's dentist office last year, where Nigora was working as a receptionist at the time, and the twice-married millionaire revealed it was love at first sight. He said: "I spotted her while getting some crowns done. Just as I was building up the courage to speak to her, the buzzer went for my appointment.
"When I went home I couldn't stop thinking about her, I felt obsessed! I felt in love with her."
Nigora has previously opened up about her feelings for Duncan, telling ITV's This Morning: "He's the most generous man I've ever met in my life… I'm very much in love."
The star was already hinting at marriage just weeks after he began dating Nigora. He exclusively told HELLO!: "Nigora and I are very much in love. We met only a few weeks ago and many people don't realise we only began our relationship after the break-up of my previous relationship had occurred."
Duncan meet Nigora during his trip to the dentist
Things haven't always ran so smoothly for Duncan, and the businessman opened up about his very public split with Michelle Evans after seven months of dating, telling This Morning that Nigora stopped him from feeling "bitter." He said: "You don't feel bitter when you're madly in love. Everything else doesn't matter. I'm just an excited schoolboy."