Actor Bradley Cooper and model Irina Shayk's relationship is reportedly getting serious.

The 40-year-old actor and the Russian model started dating last month after being introduced by Leonardo DiCaprio.

"They have been spending lots of time together these past few weeks and have had many date nights. Their chemistry is crazy when they are together. They can't keep their hands off of each other," a source close to the duo told eonline.com.

While the two are still getting to know each other, insiders believe their relationship is becoming more serious.

The source added: "Bradley thinks Irina is stunning but also such a sweet woman with a great heart. Irina is really impressed with how down to earth Bradley is and really easy to be around.

"She also thinks he is such a hardworking, talented actor. They have great conversation and so many laughs when they are hanging out. Friends of theirs would not be surprised if things got serious."

Bradley Cooper. Photo: AFP

The "American Sniper" star split from Suki Waterhouse, 23, in March after two years of dating, while Shayk, 29, and ex-boyfriend Cristiano Ronaldo, 30, ended their relationship in January after five years together.