"It's always amazing to get positive feedback from audience and it made me really happy to see the reaction. I worked a lot on myself to get the fitness needed for the film," Vaani said in a statement.
The 30-year-old actress had to undergo gruelling sessions of pilates, yoga, weight training in the gym.
"I was very excited about this project and Sid was very clear as to how he wanted me to look for the part. The toughest was the dieting and making sure there were no cheat meals but it was all worth it," she added.
"War", which stars Hrithik Roshan and Tiger Shroff is directed Siddharth Anand.
"In 'War', we wanted to cast a stunning, super fit girl as she was being paired opposite the most good looking hero of our country, Hrithik Roshan. Vaani fit the bill completely because she is an amazing actress and she put in a lot of effort to look the way she has looked in the film," Anand added.
"War" is set to be a visual spectacle for quintessential action cinema lovers as they would witness Hrithik and Tiger pull off jaw-dropping sequences while they try to beat each other.
Produced by Yash Raj Films, the high-octane film is to release in Hindi, Tamil and Telugu.
( With inputs from IANS )