His comment comes ahead of Prime Minister Narendra Modi‘s visit here on Saturday to attend the centenary celebrations of Patna University.
“He is a fake socialist. Real socialist neither joins hands with communal forces nor is afraid of them,” Lalu Prasad tweeted.
He added “Ye asal mein Godse aur Hitler ka bada wala pujari hai (He is actually a big follower of Godse and Hitler).”
In the last week of July, Nitish Kumar had dumped the RJD and Congress to join hands with BJP and form the government. In August his party JD-U formally joined the BJP-led NDA.
Lalu Prasad has earlier called Nitish Kumar the Paltu Ram of politics for breaking the Grand Alliance and forming a new government with the BJP.
Nitish Kumar had in 2013 dumped the BJP and joined hands with the RJD and Congress.