Mumbai: Megastar Amitabh Bachchan on Sunday penned a heartfelt post on social media for his son and actor Abhishek Bachchan, saying he is his "dearest friend".

"When he not just wears your shoes, but also shares the same number of chairs to sit on, then he is not just a son but your dearest friend," Amitabh wrote on Instagram along with a photograph in which the father and son are seen seated on three stacked chairs each and engaged in a serious conversation.

The photograph was taken on the sets of Big B's debut Tamil film "Uyarndha Manithan".

Abhishek too has often expressed his love towards his father on social media. Earlier this year, when Amitabh completed his 50 years in Indian cinema, Abhishek wrote an emotional note for him, calling him his "icon".

""Icon! To me, he is so much more. My father, best friend, guide, best critic, greatest support, idol - hero! 50 years today he started his journey in films. Even today, his passion and love for his craft and work is the same as I'm sure it was on the first day."

They have even shared screen space with each other. They both featured together in movies like "Kabhi Alvida Naa kehna", "Sarkar" and "Paa".

Currently, Amitabh is gearing up for the Tamil film and a fantasy film "Brahmastra", while Abhishek will be next seen in the second season of a web show "Breathe".