Rebel MLAs Gyanendra Singh Gyanu, Poonam Devi, Ravindra Rai and others told reporters that ministers and some party legislators were intimidating them.
Asked if there was any scope of sorting out differences within the party, Gyanu said, "There will be no compromise on RS poll... Any talk can be held only after June 19 voting on RS seats."
He claimed support of nearly 50 JD(U) legislators and said that the figure was going up with each passing day.
Ravindra Rai, suspended by JD(U) for a tirade against Nitish, echoed similar grievance.
Gyanu and others said they would not budge from their stand.
"We will not rest till sycophants and turncoats, many of whom have become ministers, are shown the door," they said.