Bihar Chief Minister Nitish Kumar on Tuesday accused Prime Minister Narendra Modi of demeaning the office he holds.
In a blog post, the Janata Dal-United (JD-U) leader said the words Modi was using in his election campaign were "low grade" and betrayed a "regressive mindset".
"I am surprised to see that the working of a prime minister can be so hollow and his thoughts could be so regressive," Nitish Kumar said in his Facebook post.
"This nation has never had a prime minister who made religion their identity. So I am horrified when I see Modi publicly asking for votes on the basis of caste and religion. I feel like the sacred and glorious past of the nation are being tampered," Nitish Kumar said.
Nitish Kumar is the chief ministerial candidate of the Grand Alliance of the JD-U, RJD and the Congress. The third round of voting for the Bihar assembly elections is due on Wednesday.