The 41-year-old "The Revenant" star and the supermodel, 24, are not planning on settling down, reported People magazine.
"I don't think it's any more than a fast fling," a source said.
The duo recently vacationed together with friends on the private Bahamian island Over Yonder Cay. They were also spotted together on a weekend getaway in Montauk, New York, in June.
The two were also recently spotted partying together at the Up & Down club in New York City.