Both of them have been very good friends from the childhood. In the past also there were rumours about them, but they have clarified that the rumours are not true. Also, the buzz reveals that Sai Dharam Tej is currently going to be a part of an interesting project and it will be produced by himself. The buzz is that Niharika might be playing the female lead in the film.
As of now, these are all rumours and hopefully, the rumours end soon.