Actress Vaani Kapoor, who awaits the release of her forthcoming film "Befikre" where she stars alongside Ranveer Singh, says its difficult to match up to her co-actor's "infectious energy".

"It's very difficult to match his energy. I don't know what battery he operates on... It's very unique and I love watching his energy from a distance. It's very infectious," Vaani told reporters, while promoting the film here.

Ranveer, who was also present here to promote Aditya Chopra's directorial, says that for him keeping up with Vaani's energy was tough.

"On the first day when we shot for the first scene I was like 'man I have to keep up with her...'So, yes I had to match up to her energy," Ranveer added. Releasing on Friday, "Befikre" is a romantic comedy film that has been extensively shot in Paris.