"The mover of the entire episode very politely told mediapersons that he is ignorant about the event. I wish to salute his politeness," Tiwari said in a statement.
After being denied a second term in Rajya Sabha as JD(U) nominee, Tiwari has missed no chance to take potshots at Kumar.
Tiwari praised RJD Legislature party leader Abdul Bari Siddiqui for practising "principled" politics.
"Shunning lure of Deputy Chief Minister post from JD(U) as per reports of offer to contest either Lok Sabha or go to Rajya Sabha, Siddiqui remained with RJD and strongly defended his party," he said.
Meanwhile, Bihar JD(U) President Basistha Narayan Singh told PTI that the matter was as "internal matter" of the RJD and "we have nothing to do with it."
But, the episode makes it clear that "there is discontent and murmuring within that party (RJD)", he added.