She’s filming Aquaman on the Gold Coast and training hard for her role as Queen Mera.

And on Tuesday, Amber Heard made fun of her co-star Jason Momoa for the size of his boot, holding up a picture of it on Instagram.

But it was the 31-year-old’s taut abs and sculpted arms that stole the show in the snap, with fans flocking to comment how toned and fit Amber looked.

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Who is looking at the shoe? Amber Heard made fun of her co-star Jason Momoa for the size of his boot, holding up a picture of it on Instagram, flashing her abs and trim figure

One fan wrote: ‘Looking absolutely ripped, well done on that training miss.’

Another added: ‘Even working out, you’re glowing & you inspire me to start working out again.’

Amber went makeup free and had her long locks tied into braids.

She wore a black sports bra and matching high-waisted tights.

Friends: Amber is seen here with hunky co-star Jason Momoa

Those guns! Jason is known for his ripped physique

She appeared to have just completed a workout with a personal trainer, and rested on a yoga mat.

The blonde beauty captioned the snap: ‘Check out Jason’s boot. #Aquaman’s gonna need some big flippers.’

In the film, Game of Thrones star Jason plays lead character Aquaman, who is married to Queen Mera.

Stunning: A shot of Amber in character has recently made headlines

A shot of Amber in character has recently made headlines, where she stuns with long red hair and flaunts her curves in a green skintight bodysuit.

Nicole Kidman, Patrick Wilson and Willem Dafoe also star in the film.

Amber – who was previously married to Johnny Depp – is also making headlines for her new relationship, and is currently dating Tesla founder and billionaire Elon Musk.