Deputy chief minister Tejashwi Yadav on Sunday delivered a follow-up blow on state Congress leaders by asking them if they would not be happy if a Bihari - read Nitish Kumar - became Prime Minister, two days after his father Lalu jabbed at the Congress by leaving Rahul Gandhi out of his list of PM probables.

In an exclusive interview to The Telegraph on Friday, Lalu had said he did not consider Congress vice-president Rahul Gandhi worthy of the post of Prime Minister and named Mulayam Singh Yadav, Mamata Banerjee, J. Jayalalithaa and Nitish Kumar as contenders instead.

"If any Bihari becomes Prime Minister, don't you think that it would be matter of great happiness? Won't Bihar Congress leaders be happy?" Tejashwi said after garlanding the statue of Sir Seewoosagur Ramgoolam, considered the father of the nation of Mauritius, on his birth anniversary.

"If Nitish ji becomes Prime Minister, it is obvious that even (state Congress chief and education minister) Ashok Choudharyji would be happy. Ashok Choudharyji is already working under the Nitish ji so Ashokji knows the calibre of Nitish ji."

During a recent joint press conference of Grand Alliance in which JDU state chief Bashishtha Narayan Singh and his RJD counterpart Ram Chandra Purbey were present, Choudhary had declared that Rahul Gandhi was the only Prime Minister candidate for any anti-BJP front for the 2019 elections.

Choudhary had also ribbed the RJD during the verbal war between the RJD and JDU over gangster-turned-RJD leader Mohammad Shahabuddin's release on bail, by saying that if the RJD had problems with Nitish it was free to walk out of the coalition.

Choudhary's comment had enraged Lalu, which led to the RJD chief's snub to Rahul as PM contender, and Tejashwi's comments today was a follow-up punch, RJD sources said.

"I have already said that Nitish ji is better PM (material) than Narendra Modi," said Tejashwi, who a section of the political grapevine believes will be the top contender for Bihar chief minister if and when Nitish makes a push towards Delhi. "It is certain Modiji will not become PM again in 2019 and there are many strong leaders in regional parties. As far as Rahul Gandhi is concerned, even the Congress party has not yet officially declared him as their prime ministerial candidate. Rahul Gandhi is working hard and every political party projects their best person for the top post."

When contacted, Sadanand Singh, Congress legislative party leader in the Assembly, refused to react to Tejashwi's question whether the Congress leaders would be happy if Nitish became PM. "I do not want to comment on this and I have already said on Saturday that Rahul Gandhi is our PM candidate," Singh said.

Amid the shadow boxing, senior BJP leader Nand Kishore Yadav did not let go of the opportunity to land one on the Grand Alliance.

"There is no vacancy for the post of PM now but the leaders of Grand Alliance are doing childish work by discussing this topic as if Lok Sabha election results have come out and the leader is soon to be elected," Nand Kishore said.

He claimed that the PM candidate issue was a fallout of the "cold war" between Nitish and Lalu over Shahabuddin's release in which the Congress supported the chief minister. "By calling Nitish PM material, Lalu has cut Congress leaders down to size," Nand Kishore said.