Mr Kushwaha excused himself citing his preoccupation in Delhi, even as Bihar Chief Minister Nitish Kumar, Union ministers Ravi Shankar Prasad and Radha Mohan Singh, Deputy CM Sushil Kumar Modi, BJP national general secretary in-charge of the state Bhupendra Yadav and LJP chief Ram Vilas Paswan attended the gathering.
Shortly after Mr Kushwaha conveyed his decision to skip the event to BJP state president Nityanand Rai over telephone, a statement was issued by his party's national working president Nagamani saying: "NDA will achieve spectacular success in Lok Sabha and Vidhan Sabha polls in Bihar if these are fought projecting Mr Kushwaha as the leader of the coalition".
"After the BJP, the RLSP has the largest support base among NDA constituents in Bihar. On the national level, ours is a bigger party than the JD(U) and the NDA had benefitted from Mr Kushwaha's support in the 2014 Lok Sabha polls, when JD(U) had fought separately,"Mr Nagamani said.
"Some leaders of the JD(U), and even the BJP, have acknowledged Nitish Kumar as the NDA's leader in Bihar. This cannot be deemed as the view of the entire coalition. The leader for Bihar shall be decided by the NDA's national leadership and not by those of a state level", he added.
However in an attempt to avoid confrontation, Mr Nagamani later turned up at the NDA get-together at the Gyan Bhavan complex. As he took a seat near the entrance of the hall, Mr Nagamani was persuaded by Nityanand Rai to be seated close to other senior leaders.
Discontent has been brewing among NDA constituents in Bihar, who face the daunting challenge of arriving at a seat-sharing formula acceptable to all.
Out of the 40 Lok Sabha seats in the state, the BJP won 22 in the 2014 polls, while the LJP and the RLSP bagged six and three respectively.
The JD(U) fought separately and won only two. However, the party has been pushing its status as the "senior coalition partner" in the state, pointing towards its greater number of lawmakers.
"We contested 25 seats in 2009 and we should get the same number this time. It would be our right and not a charity,"Mr Rajak told reporters at Gyan Bhawan complex.
Mr Tyagi said in Delhi that if 2014 results were to be taken as a benchmark to allot seats to each NDA constituent in 2019, "then in the 2020 assembly polls, the results of 2015 should be taken as the base and JD(U) should be given 150 out of the total number of 243 seats".
Mr Kushwaha, a former Nitish Kumar loyalist, had quit the JD(U) in 2013 when he was a Rajya Sabha member, months after having been suspended from the party on disciplinary grounds.
He went on to form his own party and joined the BJP-led NDA. Riding the strong Narendra Modi wave in 2014, his party won three Lok Sabha seats and he became the minister of state for human resource development.
However, his party did poorly in the assembly polls a month later, managing to win only two seats. He has reportedly been sulking over his diminished stature in the NDA since Mr Kumar returned to the coalition last year.
The NDA gathering is first since Mr Kumar returned to the coalition after dumping the Grand Alliance with the RJD and the Congress in July last year.
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