Pregnant Margot Robbie and Tom Ackerley enjoy the most exclusive party in the Mediterranean while vacationing on a $250 million superyacht with Gigi Hadid, Bradley Cooper and Benedict Cumberbatch

Margot Robbie, Gigi Hadid and Bradley Cooper were among the guests at the most diverse party in the Mediterranean while holidaying together this week.

Hollywood's elite proved that this summer's most exclusive gathering took place at sea as they relaxed with their children on a $250 million superyacht.

Pregnant actress Margot, 34, who is expecting her first child with husband Tom Ackerley, was seen with celebrity power couple Gigi and Bradley.

The group of stars was joined by fellow actor Benedict Cumberbatch, who was also spotted on board the luxury ship called Multiverse.

Multiverse is a 350-foot (116 m) yacht launched in 2018 by Kleven Maritime AS of Norway and is considered the 50th largest yacht in the world.

Margot Robbie, Gigi Hadid and Bradley Cooper were among the guests at the celebrity party in the Mediterranean while vacationing together this week.

Pregnant actress Margot, 34, who is expecting her first child with husband Tom Ackerley, was seen with celebrity power couple Gigi and Bradley

The yacht accommodates up to 30 guests in 15 cabins and can also carry up to 36 crew members on board to ensure a relaxed luxury yacht experience.

Away from the group, Gigi and Bradley were spotted relaxing on one of the decks of the spacious yacht and sharing a few tender moments together.

The couple, who first became romantically linked in October last year, hugged and kissed in a shady area.

The stars also enjoyed a lighthearted chat while the Silver Linings Playbook actor sipped a warm beverage.

Gigi wore a chic orange bikini for the day on the water, and when she wasn't swimming, the beauty wore a semi-sheer white overdress over the swimsuit.

Her short blonde curls fell naturally, almost touching the tops of her shoulders, and she also opted for fashionable sunglasses.

Bradley also kept it casual, wearing a sleeveless grey shirt and dark green swim trunks.

He was also accompanied by his seven-year-old daughter Lea, whom he has with his ex and supermodel Irina Shayk.

On Thursday, the couple reached a milestone in their relationship when Gigi was spotted with Lea for the first time as they landed in Sardinia – and the actor's mother, Gloria, was also there.

At one point away from the group, Gigi and Bradley were spotted sharing a few tender moments together while lounging on one of the decks of the spacious yacht

The Oscar winner enjoyed the last days of summer with the supermodel, who was seen for the first time with his seven-year-old daughter Lea during the relaxing holiday.

They emerged together from a sleek black SUV after arriving on the island of Palmarola by private jet.

At this point, Margot was already spending time with her husband Tom on the luxurious yacht.

She showed off her baby bump in a black bikini – after it was confirmed last month that the couple are expecting their first child together.

And on Saturday, the Barbie actress was spotted again joining Bradley and Gigi on the big boat.

The expectant mother showed off her growing belly in a black bikini top and a short-sleeved black top that was open at the front.

Her blonde curls were parted in the middle and fell effortlessly in light waves over her shoulders.

On one of the yacht's upper decks, Hadid and Robbie were seen chatting while Bradley and Tom sat nearby.

Later in the day the group left the yacht and some had a lot of fun on a speedboat on the water.

Hadid also wore a life jacket and then got under an outdoor shower with Bradley.

Cooper enjoyed some time alone, got some exercise on a canoe and paddled to a sandy beach where he also took a quick swim.

Bradley and Gigi were first romantically linked in October last year