Releasing on May 18, 'Department' stars Amitabh Bachchan, Sanjay Dutt and Rana Daggubati in lead roles besides Anjana and Telugu actresses Madhu Shalini and Lakshmi Manchu.
During the film's promotions, Varma was seen with the lead male actors at all events.
Also, RGV is said to be praising Brazilian-Indian model Nathalia Kaur who has performed an item number 'Dan Dan' in the movie.
This apparently has not gone down well with Singh, who plays a negative character in the film.
"I don't know why I haven't been promoted despite giving 100 percent for the film. I am upset... Feeling bad. Also it is not that I am playing some small character, my role is also important. I don't know why I have been kept away. I have no clue," Singh told PTI.
Earlier, he worked with RGV in 'Rakht Charitra', where his character of Bukka Reddy was the one audiences loved to hate. Also, he would be seen next in 'Ab Tak Chhappan' sequel, a 2004 film produced by Varma.
However, the actor who has always played a baddie has done an item song in 'Department'.
"It is not a typical item number. It goes with the story... There are lots of other things happening in the background, like there are action scenes going on. The sad part is that I heard it through someone that this song has been chopped from the movie," Singh said.
"I am waiting for the film to release and see whether the song is there or not. If its not, then why so," he asked.