Mariah Carey and James Packer eye Tahiti for wedding

Wedding plans are already in full swing for Mariah Carey and her Aussie billionaire beau James Packer after their January engagement — and while Carey’s being coy, sources tell Page Six the nuptials could take place in Tahiti and involve Packer’s beloved superyacht.

Carey hinted this week, “I’ve picked a lot of things that I can’t tell,” and, “It’s not going to be a big wedding, but it’s going to be grand . . . I’m most excited about the grandeur, darling.”

Insiders are buzzing that Carey and Packer plan to tie the knot in Tahiti, where Packer’s been known to sail his 287-foot converted icebreaker Arctic P, one of the world’s most luxe yachts. It will be the third marriage for both.

Polynesia’s been popular with Hollywood celebs lately. Last year, Jennifer Aniston and Justin Theroux honeymooned in Bora Bora after their secret LA wedding.

Carey’s rep huffed that any Tahitian wedding plans were “definitely all rumors.” The rep previously said the singer’s busy schedule — including her Las Vegas residency and an upcoming world tour — will likely put wedding plans on hold.

Carey, however, boasted this week that she’s already making the plans and “certain things about it [are] going to be grand. The most important thing about it is the relationship and the connection and the love of it all, but of course I love a grand moment. But we’re not going to have tons of people and stuff like that. It’s very private,” she told “Access Hollywood.”

One wrinkle: The lovebirds are not yet divorced from their exes. Mariah’s still finalizing her split from Nick Cannon, while Packer and his ex, Erica, are still wed, according to a report, although they split in 2013 and Erica is dating singer Seal.

Packer popped the question to Carey in January with a 35-carat diamond ring reportedly worth more than $7 million. “Walking through a crowd wearing a ring on your finger and a lot of bracelets is a little daunting, but it’s hard to take it off because I love it so much,” Carey said about performing with her rock. The couple plans to split their time between New York and LA.