A new Defence Minister is expected to be given charge on Sunday morning when Prime Minister Narendra Modi is likely to revamp his cabinet in a big shake-up. Arun Jaitley will retain the Finance Ministry; he currently holds charge of both key departments. Transport Minister Nitin Gadkari could also get charge of the crucial Railways ministry, sources said, and the present Rail minister Suresh Prabhu will be shifted to another department. Law minister Ravi Shankar Prasad is likely to get a new assignment. Prime Minister Narendra Modi is still tweaking the list and the final shape of the new-look cabinet is likely to be ready tonight, sources said.