Lady Gaga and Bradley Cooper's exes, Christian Carino and Irina Shayk bond on Instagram

A Star Is Born lead characters, Bradley Cooper and Lady Gaga's exes have been spotted bonding on Instagram.

Irina Shayk, Cooper's now ex-girlfriend, posted a sexy swimsuit photo following their break-up.

Sharp-eyed fans of the ex-couple caught out Gaga's ex-fiance, Christian Carino, giving Shayk's photo a double tap with a noticeable "like" on Instagram, reports the New York Post.

In Shayk's Instagram photo, she is posing next to a waterfall in a booty revealing black one-piece swimsuit.

Shayk does not follow Carino on Instagram — but maybe she will soon.

Gaga and her ex-fiance called off their engagement in February this year around the same time romance rumours sparked between the A Star Is Born co-stars.

The pair not only star as a desirable couple in the movie, but they also shared mouth-dropping performances during award season due to the intimacy of the pair.

To add fuel to the fire, the blockbuster film stars were seen to be all over one another in various interviews and at promotional events.

Shayk, who shares 2-year-old daughter Lea De Seine with Cooper, has been in the public eye ever since the New York Post exclusively revealed last week that the couple's relationship was "hanging by a thread."