Bihar Chief Minister Nitish Kumar will prove to be the best prime minister if the factors are favourable in 2024, though his JD(U) would not insist on the top post for him at the cost of Opposition unity, a top party leader said on Sunday.

JD(U) parliamentary board president Upendra Kushwaha, however, ducked queries as to who would be the successor if the state's longest serving chief minister were to move on to the national stage.

"Nitish Kumar will be the best prime minister, provided circumstances are in his favour. We are, however, not going to make any claim and put prospects of a united opposition in jeopardy," Kushwaha told reporters at the JD(U) office.

The former Union minister, who returned the previous day after spending more than a week out of station, expressed bewilderment over frantic speculations that he was upset over not being inducted into the new cabinet headed by Kumar.

"Please take it on record and confront me if I ever go back on my words. I am never going to become a minister in the state. Doing so will be demeaning to me," he said.

Kushwaha, who returned to the JD(U ) last year, merging the RLSP which he had floated in 2013 after breaking away with Kumar, said he was a minister at the Centre, an MP in both Lok Sabha and Rajya Sabha, an MLA and is currently an MLC.

"A state cabinet berth is not of much significance to me. I do believe that our leader (Nitish Kumar) is the best person to lead the campaign to preserve the socialist ideology. My only focus, as of now, is to establish our party and our leader by 2024," he said.

The next Lok Sabha election is due in 2024.

Asked whether he saw himself or Deputy CM Tejashwi Yadav of the RJD as a successor to Nitish Kumar, were the veteran leader to move to Delhi after the Lok Sabha polls, Kushwaha said it was a hypothetical question that he would not like to entertain.

Kushwaha, who was in the NDA a few years ago, but has emerged as one of the most virulent critics of the BJP since his return to JD(U), also slammed the saffron party for alleging that jungle raj has returned to Bihar following the chief minister's realignment with the RJD.

"That is the problem with the BJP. All is hunky dory till you are with them. The moment you part ways, all hell breaks loose. Till Nitish Kumar was with them they were showering praises on him. Prime Minister Narendra Modi was calling him the epitome of socialist values. But now the same Nitish Kumar has become most despicable for them," he added.

Kushwaha maintained that the JD(U) was the victim of a conspiracy in the 2020 Assembly polls when its tally fell drastically, blamed largely on the rebellion of the LJP's Chirag Paswan and a botched up ticket distribution by RCP Singh, both of whom have been accused of being BJP agents .

He also dismissed allegations of tainted ministers in the new cabinet, claiming that many BJP cabinets in other states had people named in serious cases.

Kushwaha also expressed displeasure over allies like former chief minister Jitan Ram Manjhi suggesting that Nitish Kumar sack such ministers for the sake of his reputation.

"Nitish Kumar is more experienced than most others. He does not need anybody's advice," he said.

The JD(U) parliamentary board chief also frowned upon MLA Bima Bharti going public with her grievances over Leshi Singh's induction into the cabinet.

"Her allegations against Leshi Singh have been rightly rejected by the CM. Even if there were an iota of truth in her allegations, it was not proper on her part to issue statements to the effect in the media," said Kushwaha.

Bharti had alleged that Leshi Singh was involved in a murder.