Congress leader Sanjay Nirupam was issued a show cause notice by the Election Commission on Tuesday for his "modern-day avatar of Aurangzeb" jibe against Prime Minister Narendra Modi.
He has been given 24 hours to respond.
The Commission said that prima facie, Nirupam has violated the provisions of the model code by making the remarks.
"The people of this constituency chose a person (PM Narendra Modi) who is actually the modern-day avatar of Aurangzeb. Because in Varanasi, in the name of corridors, hundreds of temples have been demolished on the instruction of Prime Minister Modi," Nirupam had said at a public meeting in Varanasi last Tuesday.