"Our alliance is intact... members of the coalition worked together in the Maharajganj by-election," Kumar said, dismissing suggestions of rift within NDA.
"NDA workers laboured hard sincerely in Maharajganj bypoll," he told reporters at PatnaAirport on return from Delhi.
The defeated JD-U candidate in Maharajganj P K Shahi had said on Wednesday that there was lack of enthusiasm among some NDA workers and lack of poll management which cost the poll.
This set the tongue waging that BJP workers did not worked hard for victory of Shahi due to JD-U's opposition to Narendra Modi which has resulted in bickering among leaders of the two NDA partners.
Nitish Kumar is chairman of NDA in Bihar and BJP leader and minister Nand Kishore Yadav is the convenor.
He said Maharajganj bypoll result was no cause of worry for him. "Maharajganj seat was with RJD which they have retained. There is nothing to go euphoric about it," he said.
On RJD President Lalu Prasad taking potshot at him on the defeat of JD-U candidate by over 1.37 lakh votes in Maharajganj, Kumar, who is senior JD-U leader, said: "Let RJD be on cloud nine...this jubilation is short lived."
Seeking to take virtue out of the defeat, he said, "Though we lost, the vote percentage of JD-U has increased in the bypoll from that in last General election and Assembly elections in 2010."
"The JD-U had won only 5 seats out of 18 Assembly seats in by-elections in 2009. But, the people voted JD-U and BJP to a record victory in 2010 Assembly polls and RJD faced humiliating defeat," he said, seeking to play down political impact on 2014 parliamentary elections.
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