Siddhant will be lending his voice to the character of Chris Hemsworth and Sanya will voice for Tessa Thompson's role.
"This cult franchise is a global phenomenon and has set a benchmark for sci-fi comedy films. I have been a fan of the films since childhood and extremely very happy to join the MIB family," Siddhant said in a statement.
"Chris Hemsworth is a global icon and I have been religiously following him since his superhero days. To voice for his character is a dream come true and I hope with this project, I manage to live up to audiences' expectations and sustain MIB's legacy in India," he added.
The action-adventure spin-off "Men in Black: International" introduces two new MIB members: Hemsworth as Agent H and Thompson as Agent M.
Sanya says she "has thoroughly enjoyed 'Men in Black' movies and have always been a huge fan of the stylish action and humour".
"I am very happy that I got the opportunity to voice for Tessa's character in 'Men In Black: International' and be a part of this franchise in my own special way. She is really headstrong and fierce, something I relate to. This has been a unique and challenging experience and I hope my fans will appreciate this new venture from me," she added.
Sony Pictures Entertainment India will release "Men In Black: International" in India on June 14 in Hindi, English, Tamil and Telugu.
( With inputs from IANS )