Prasad was seated on the dais when Kumar spoke about his parting ways with the RJD chief.
The senior JD(U) leader said this time he has joined forces with Prasad to keep the resurgent BJP away from power in Bihar during 2015 assembly polls.
Charging the Modi government at the Centre with being arrogant, he said the grand alliance of the RJD, JD(U) and Congress will give "medicine" to BJP from Bihar.
Prasad rued that the secular forces lost the general elections due to division of votes, but said no such mistake will be committed this time as the three major parties - RJD, JD(U) and Congress - have come together to stop BJP's juggernaut.
"BJP won due to division of votes of secular parties ... We polled 1.60 crore votes in the general elections and BJP less than us (in Bihar), but yet it walked away with lion's share of seats (31 out of 40) in partnership with LJP and RLSP," the RJD supremo said.
"This time we will put BJP in its place after stitching together votes of RJD, JD(U) and Congress," he said.