Bradley Cooper and Irina Shayk officially break up

Irina Shayk and Bradley Cooper at the Golden Globe Awards in January this year. Photo / Getty Images

Hollywood actor Bradley Cooper and his partner, Russian model Irina Shayk have split after four years of being together.

Cooper, 44, and Shayk, 33, have officially decided to end their relationship, according to People.com.

They are reportedly working out how to share custody of their daughter Lea De Seine, who they welcomed in March last year.

Their relationship was reportedly on the rocks, with reports fron The Sun that the couple were recently living separately.

Shayk was understood to have moved out of Cooper's $6.55 million Pacific Palisades house with their two-year-old daughter.

A source close to the couple had told The Sun: "Things are cooling off between Bradley and Irina in a big way.

"They haven't been good for a few months and Irina decided it would be best if she moved into her own place.

"It's not looking like there's much long left for the two of them together."

US reports earlier this week revealed the pair's relationship was "hanging on by a thread".

Cooper was linked to Lady Gaga, 33, earlier this year after their electrifying performance at the Academy Awards stunned the world.

Oscar-nominated Cooper performed a sexually-charged duet of Lady Gaga's song Shallow from their hit movie A Star Is Born.

Lady Gaga and Bradley Cooper's performance at the Academy Awards stunned the world. Photo / Getty Images

The pair's onstage chemistry at the Oscars sent social media into a meltdown.

Lady Gaga was forced to defend the performance, saying it was all an act.

"(Shallow) is a love song, A Star Is Born is a love story," Gaga said.

"It was so important to both of us that we were connected the entire time … When you're singing love songs, that's what you want people to feel."

Cooper and Shayk's break up comes as Lady Gaga also recnetly split from her fiance Christian Carino.

Lady Gaga (right) recently split from her fiance Christian Carino. Photo / Getty Images

Gaga and Carino revealed in February they had called off their engagement after two years of dating.

Over the weekend, she told fans at a performance of her song Someone to Watch Over Me at her residency in Las Vegas she would be singing her song without a ring on her finger.

"Last time I sang this song I had a ring on my finger," she told the crowd.

"So it will be different this time."