Actor Hrithik Roshan says he is very impressed with his elder sister Sunaina Roshan's impressive transformation.

Hrithik on Thursday shared a before and after photograph of his sister. In one image, which seems to be a little old, Sunaina is seen to be in a more voluptuous size, while in the current photograph she is seen in a svelte body sporting a ravishing black dress and a beautiful pearl necklace.

"Now that's what I call a transformation! So so proud of you didi (elder sister) Sunaina Roshan. Keep going, impossible is nothing," he captioned the image.

Now that's what I call a transformation !! So so proud of you didi @roshansunaina #keepgoing #impossibleisNothing pic.twitter.com/yQA4OZ4N9K

— Hrithik Roshan (@iHrithik) September 7, 2017

On the acting front, Hrithik, who was last seen on the silver screen in "Kaabil", will reportedly be seen in Vikas Bahl's biopic film on "Super 30", based on mathematician Anand Kumar.