Bradley Cooper and Zoe Saldana get cozy at Sundance Film Festival

(CBS/AP) PARK CITY, Utah - Bradley Cooper and Zoe Saldana came to the Sundance Film Festival to promote their closing-night film, "The Words," and the actors reportedly went public with their rumored off-screen romance while there.

Cooper and Saldana play a married couple in the film, which follows an aspiring writer who gains fame when he finds an old manuscript and passes it off as his own.

Pictures: Sundance Film Festival 2012
Pictures: Bradley Cooper

People reported Tuesday that the couple was seen getting cozy at a cocktail party for their movie.

"They were kissing in front of the fire and being very affectionate," an onlooker told the magazine, while another source said, "They are definitely very together."

However, the pair avoided any appearance of the reported relationship by staying apart from one another while posing for photos and giving interviews to support the film, according to the Associated Press. Saldana did affectionately touch Cooper as they passed in a hallway, though.

Saldana "amicably separated" from entrepreneur fiance Keith Britton in November, after 11 years together. Cooper previously dated Renee Zellweger for two years (they split back in March), and was rumored have dated Jennifer Lopez last fall.

"The Words," which also stars Dennis Quaid, Jeremy Irons, Ben Barnes and Olivia Wilde, premiered Friday. It was acquired early in the festival by CBS Films, which plans to release it theatrically in the fall. Sundance continues through Sunday.