The pair are currently filming their new movie "The Other Woman" and kiss was for a scene in it.
But the actors' proximity on and off the sets is giving a tough time to Gaga, who is recovering from her hip surgery, reported Contactmusic.
"This isn't going down well. Cameron and Taylor have clicked on set and are getting on really well. They've been hanging out and the news has reached Gaga's camp. It's been a stressful time for Gaga with this on her plate as she's recovering from hip surgery," a source said.