A sequel to the 2007 hit "Welcome", Anees Bazmee's "Welcome Back" also stars Shruti Hassan.
"John is one star who is so normal and so down to earth. He is so humble and co-operative," Sambhavna said in a statement.
"He has no starry tantrums and it's very easy to talk to him. He's a great person," she added.
Titled "Main Babli hui tu Bunty hua", the song has been composed by Anu Malik, while Ganesh Acharya has choreographed the song.
Sambhavna, who has done item numbers such as "Chala kafila tere naam ka" and "Aashiqui mein teri", came into the limelight after participating in the controversial reality show "Bigg Boss 2".
"I'm happy and confident, I'm doing item numbers because I don't mind them. Dancing is a blessing and I'm good at it. I worship my work and art and I am proud of all that I'm doing and all that I've done," she said.
