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Chief among the many reasons why Mr Kumar is upset with the BJP, which is an alliance partner of the Janata Dal (United), or JD(U) in Bihar, has been the BJP-led central government's offer of token representation to allies as Union Ministers.
Mr Kumar's party had denied another Rajya Sabha berth last month to his former JD(U) colleague RCP Singh, who had taken a spot in Prime Minister Narendra Modi's cabinet last year without consulting Mr Kumar. Mr Singh bade farewell to the JD(U) over the Rajya Sabha snub.
"There's a conspiracy against me because I'd become union minister," said Mr Singh, a former Indian Administrative Service officer who was once the national president of JD(U). "I'll just say that there's no cure to jealousy," he said while leaving the JD(U) yesterday. "Nitish Kumar will not become Prime Minister in any of his seven lives," he said, describing the JD(U) as a sinking ship.
Mr Kumar reacted by sending out his party's top leaders to respond to allegations by Mr Singh of pettiness and for allegedly dragging his family into a political fight citing illegal property deals.
The JD(U) national president Rajiv Ranjan (Lalan) Singh in a hurry to blunt the attacks by Mr Singh, however, appeared to have overcorrected when he ended up threatening the alliance party BJP.
"What is the need to join the Union Cabinet? The Chief Minister had decided in 2019 we won't be part of the Union Cabinet," Rajiv Ranjan told reporters. He said the JD(U) won't join the Union Cabinet in the near future too, leading to speculation of a rift that can't be mended.
The sudden increase in outburst of Mr Kumar's aides like Rajiv Ranjan is seen as a calculated move to put pressure on the BJP to concede to the Chief Minister's demands, which includes removal of Bihar assembly Speaker Vijay Kumar Sinha, for whom Nitish Kumar's dislike is an open secret.
The Chief Minister, citing health reasons, had stayed away from a meeting of the government think-tank NITI Aayog in Delhi this weekend, which 23 Chief Ministers including West Bengal's Mamata Banerjee had attended. The absence was seen as yet another show of anger by Mr Kumar at the BJP.
Mr Singh had denied the charge of negotiating directly with the Modi government for a ministerial position in the centre. He said Home Minister Amit Shah had spoken to Mr Kumar about cabinet expansion and offered one berth to the party on the condition that Mr Singh himself become a Union Minister.
Mr Singh also denied the JD(U)'s allegations that there are irregularities in his property deals. "These properties belong to my wife and other dependents, who have been paying due tax since 2010," he said. "I don't know what the party wants to investigate. I have nothing to hide," he said.
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