"Leaders of parties opposed to Congress and BJP will be meeting in Delhi on February 5 to discuss the issue of giving a shape to formation of a new block of like-minded parties in Parliament," Kumar, who will participate in the meeting, told reporters after a function to launch Food Security Law in Bihar.
He said Left Front is taking initiative for formation of this new "block" and JD-U is extending support to it.
Kumar, who is driving force of JD-U, refused to identify the leaders who will be meeting in the national capital on February 5.
But, sources in the party said it would include leaders of erstwhile "Janata Parivar" like SP Mulayam Singh Yadav, JDS H D Deve Gowda, BJP Naveen Patnaik, Sharad Yadav and Nitish Kumar of JD-U and leaders of CPI and CPM.
Indicating beginning of the process of formation of the new block, Kumar said many of the leaders have evinced interest in this new grouping.
Kumar categorically ruled out any chance of JD-U returning to NDA.
"Koi Sawal hi nahi utha hai (the question does not arise)," he said in reply to a question in this regard.
The Bihar CM also dismissed party chief Sharad Yadav making any statement against formation of this new block. A section of media had quoted Sharad Yadav as saying on Friday that formation of a new block is just a "gupbazzi" (gossip).
"I had a talk with Sharad Yadav this morning and he denied saying anything of this kind...some mediapersons might have thrust words in his mouth," Kumar said.
There are reports of the CPI and CPM fighting the coming Lok Sabha elections in Bihar with JD-U.
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