Nitish alleged that to accommodate Modi, BJP president Rajnath Singh even changed party slogan in just half an hour.
"Just see how the president of that party has to change the slogan in just half and hour to eulogise him," Kumar told reporters at Patna Airport.
He was referring to Rajnath Singh's changing party slogan on the party's website in favour of Narendra Modi to drive home his point.
A tweet by Rajnath Singh yesterday with the slogan "Time for change, time for BJP" raised a storm as it was a departure from the ubiquitous party posters that show prime ministerial candidate Narendra Modi with the message 'Ab ki bar Modi sarkar (Time now for Modi government)'.
Empathising with senior BJP leaders who, he said, were "insulted" within the party, Kumar yesterday said that L K Advani had been "imprisoned" in Gandhinagar.
He had also expressed sympathy for old guard Jaswant Singh, Murli Manohar Joshi and Lal Muni Choubey, to focus on the dictatorial attitude of the BJP key leader.
He brushed aside poll surveys and said he could not see any wave in favour of BJP.