He has long been considered one of Hollywood's most eligible bachelors.

But Leonardo DiCaprio proved he was firmly off the market on Wednesday with a romantic stroll with Al Pacino's step-daughter Camila Morrone, who could not resist lavishing him with affection for the low-key outing.

The 43-year-old actor and his 20-year-old squeeze walked arm-in-arm after a breakfast date in West Hollywood during which she placed a tender kiss on his arm.

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Happy couple: Leonardo DiCaprio proved he was firmly off the market on Wednesday with a romantic stroll with Al Pacino's step-daughter Camila Morrone, who could not resist lavishing him with affection for the low-key outing

Leo kept it low-key in a navy hooded top pulled up over his head, Dodgers baseball cap and shades, which he paired with jeans and white trainers.

His Argentinian model companion meanwhile wore loose-fit distressed black jeans with slip-on heels.

She showcased some cleavage in a scoop-neck white tee, and finished the look in a wide-brimmed hat, letting her brunette tresses flow loose.

The couple weren't afraid of putting on PDA, as she kissed his shoulder before heading into the restaurant.

Taken: The 43-year-old actor and his 20-year-old squeeze walked arm-in-arm after a breakfast date in West Hollywood during which she placed a tender kiss on his arm

Incognito: Leo kept it low-key in a navy hooded top pulled up over his head, Dodgers baseball cap and shades

Happy days: Camila joined her step-father on the red carpet at the Manglehorn film premiere at the 71st Venice International Film Festival in 2014

Camila, whose stepfather is Hollywood legend Al Pacino, has been dating the Titanic star since the start of the year.

The Oscar-winner is notoriously private about his relationships, but this public outing suggests the two are getting a little more serious.

According to Us Weekly, the duo were originally just 'old family friends', the connection being Camila's mother Lucila Solá dating Leo's pal Pacino.

Chill: He paired it with jeans and white trainers

Hot: His Argentinian model companion meanwhile wore loose-fit distressed black jeans with slip-on heels

Gorgeous: She showcased some cleavage in a scoop-neck white tee, and finished the look in a wide-brimmed hat, letting her brunette tresses flow loose

Leo's little black book reportedly contains the numbers of the likes of Nina Agdal, Kelly Rohrbach, Blake Lively, Rihanna, Gisele Bündchen, and Bar Refaeli.

Earlier this week, Felicity Huffman defended the environmentalist's expensive travel habits, saying the good he does for the cause greatly outweighs any damage he is doing.

'I think Leonardo Di Caprio has probably done more for the environment than anyone. Does he fly privately? Probably but who cares?' she told DailyMail.com

'But he is doing amazing work, and really getting the message out there.'

Surveillance: Leo checked if the coast was clear before emerging

2018: Camila, whose stepfather is Hollywood legend Al Pacino, has been dating the Titanic star since the start of the year

Stepping out: The Oscar-winner is notoriously private about his relationships, but this public outing suggests the two are getting a little more serious