Paul Wesley and Girlfriend Natalie Kuckenburg Spend Luxury Yacht Day with Liam Payne and Kate Cassidy

Paul Wesley and girlfriend Natalie Kuckenburg are soaking up the sun. 

The pair spent Sunday on a luxury yacht in Saint-Tropez celebrating Wesley’s 41st birthday. They were joined by Liam Payne and his girlfriend, influencer Kate Cassidy, for a day of relaxation. 

The Vampire Diaries star sported navy blue swim trunks while his model girlfriend, 23, wore a black and white zebra print bikini. Later in the day, Kuckenburg was seen watching the sunset with her beau in a black bikini. 

Payne, 29, hopped on board to join his buddy in a blue and white collared shirt and white pants, while Cassidy, 24, wore a strapless white floral sundress. 

Though it's unclear when Wesley and Kuckenburg started officially dating, they were first spotted together in November 2022 as they enjoyed a romantic dinner date in Nerano, Italy.

After they were photographed sharing a kiss, they each posted photos from the same location on their Instagram accounts shortly after.

The actor was previously married to Ines de Ramon. After three years of marriage, Wesley and de Ramon announced their separation in September in an exclusive statement to PEOPLE.

"The decision to separate is mutual and occurred five months ago. They request privacy at this time," a rep for the couple said at the time.

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Payne and Cassidy, meanwhile, made their red carpet debut in October at the British Fashion Awards, and later attended Louis Tomlinson's All of Those Voices documentary premiere months later.

“What a crazy eye opening experience! … I’m so glad I got to share those moments with you watching your best friend, even the tearful ones,” Cassidy captioned an Instagram post from the event in March. “@louist91 well done on such a beautiful film that everybody will love🤍.”

The foursome weren't the only celebrities vacationing in Saint-Tropez this week.

Leonardo Dicaprio and his longtime friend Tobey Maguire were spotted enjoying their time on a yacht in Saint-Tropez on Thursday.

The Oscar winner, 48, was seen shirtless, sporting blue board shorts and a silver pendant necklace, as he jumped off the deck into the Mediterranean.

Maguire, 48, joined him on the sizable boat, also going shirtless and soaking up some sun. The Spider-Man actor wore a similar bathing suit, which he accessorized with a baseball cap and a pair of sunglasses.