Lupita Nyong'o and Scarlett Johansson are reportedly in talks to join The Jungle Book.
Mandela: Long Walk To Freedom star Idris Elba has already been cast in the movie, voicing Shere Khan, the man-eating tiger.
According to The Hollywood Reporter, Oscar-winning actress Lupita is in final negotiations for Raksha, the mother wolf who adopts the young boy Mowgli.
Scarlett is in the early stages of talks to voice the hypnotising python Kaa, it added.
An actor has not yet been cast as Mowgli for the reboot of the much-loved 1967 animated Disney film.
The new movie, also made by Disney and directed by Jon Favreau, is set to combine live-action and CGI and is due out in October 2015.
It is one of two projects underway, with Andy Serkis set to direct a version of Rudyard Kipling's Jungle Book being developed by Warner Bros.