Mariah Carey and James Packer attend the 2016 G'Day Los Angeles Gala Credit: Jonathan Leibson/Getty Images

Upstaged by her own bling! Mariah Carey and fiance James Packer made their first public appearance as an engaged couple on Thursday, January 28, at the G'Day USA event at Los Angeles hot spot Vibiana.

And while Carey looked stunning in a figure-hugging black dress, alongside her similarly hued husband-to-be, there was something even more eye-catching than the 45-year-old diva on last night's red carpet: her enormous engagement ring!

The future bride kept her left hand in view, and fully extended, as she rested it proudly on her thigh, allowing the whopping 35-carat diamond and platinum sparkler to do just that.

"She was proudly flashing that ring around," a fellow event guest tells Us Weekly. "Her ring totally overpowered her black dress."

Once off the red carpet (where a loved-up Mimi refused to be parted from her beau, despite calls from photographers for a solo shot), the excited couple walked into the venue, hand in hand, and took their seats for the star-studded evening that is part of Australia's trade mission to the USA.

The "Hero" singer spent time schmoozing alongside Packer, chatting to Australian dignitaries including politician Julie Bishop, MP, and her husband, Neil Gillion, before watching stars such as Seal and Hugh Jackman do their performances.

But while Carey's eyes were on the stage, her mind was evidently elsewhere.

"She was playing with her ring and twirling it around on her finger. All night," our spy reveals. "She doesn’t bend her finger. It’s like she’s proudly putting it on display."

Something that even got her an onstage mention!

“May I say James Packer and Mariah, that you’ve taken an Australian-American engagement to a whole other level?" Bishop said as she made her address. "Best wishes for a happy engagement!” she added.

If the Grammy-winning songstress' relationship with the billionaire sounds like the stuff of dreams to you, Carey wouldn't disagree. During an interview with Diana Madison of The Lowdown, Carey replied, "Let's go with 'fantasy,'"when asked to describe her new romance. 

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