Both Lalu Yadav and his son Tejaswi believe Bihar Chief Minister Nitish Kumar is would be a good PM.
Bihar Deputy Chief Minister Tejaswi Yadav on Sunday endorsed his father and RJD chief Lalu Prasad Yadav's support to Chief Minister Nitish Kumar as the prime ministerial candidate of the opposition in the 2019 general election.
"(Congress Vice-President) Rahul Gandhi is prime ministerial material but it will give me more happiness if Nitish Kumar becomes the next Prime Minister," the cricketer-turned-politician told the media in Patna.
Mr Yadav said he was "certain that Narendra Modi will not become the Prime Minister again after the 2019 general election".
Early this month, Mr Yadav said Mr Kumar is "more capable than Modi to become the next PM".
"Nitish Kumar is PM material. He is more capable than Modi to become the next Prime Minister," Mr Yadav had told newspersons.
Earlier, Mr Yadav described Mr Kumar as his "political guru" and admitted that he had been learning from the Bihar Chief Minister.
Interestingly, Rashtriya Janata Dal chief and former Chief Minister Lalu Prasad on Saturday backed Mr Kumar over Rahul Gandhi for the prime ministership.
Lalu Prasad said he was unaware if Mr Gandhi was prime ministerial candidate for the Congress in the 2019 general election. "Nitish Kumar is the PM material," he added.
Lalu Yadav's contention found immediate support among Janata Dal-United leaders.
"Lalu understands the people's pulse. He is right in saying that Nitish is prime ministerial material and a PM candidate for the next Lok Sabha polls," senior JD-U leader Shayam Rajak said.
Nitish Kumar has been emerging as the leader of non-Bharatiya Janata Party (BJP) parties to ensure a Sangh-free India, Mr Rajak added.
As expected, the Congress differed with its two allies in Bihar over the issue, saying Rahul Gandhi is the face for the top post in the next parliamentary polls.
There is strong speculation in political circles in Patna that Nitish Kumar, also the JD-U national president, is keen to be projected as the prime ministerial candidate of a united opposition against PM Modi.