The RJD's assertion came as Yadav finally made an appearance in the state Assembly after failing to attend the ongoing Monsoon Session for four consecutive days till Wednesday. On Saturday, the cricketer-turned-politician had clarified on Twitter that he had been undergoing treatment.
Following the Rashtriya Janata Dal (RJD) Lok Sabha elections debacle and Yadav's long absence from the state thereafter demands have been growing for his resignation.
Leaders of other parties as well as ally Congress in the Assembly want Yadav to follow in the footsteps of their party chief Rahul Gandhi who stepped down from his post taking responsibility for his party's defeat in the Lok Sabha polls.
RJD spokesperson Bhai Virendra said: "Tejashwi is not a leader who will leave the responsibility of leading the opposition midway."
He was replying to Congress legislator Rajesh Kumar who said Yadav should learn from Gandhi and make way for a change in the leadership in order to strengthen the Grand Alliance in Bihar. "If Tejashwi resigns, all party legislators will resign along with him," Virendra said.
On Wednesday, Lok Janshakti Party (LJP) MP Chirag Paswan had demanded Yadav's resignation as the Leader of Opposition alleging the younger son of RJD chief Lalu Prasad was not performing his duties.
Bharatiya Janata Party (BJP) leader Sanjay Maunkh also demanded Yadav's resignation on moral grounds taking responsibility for the defeat of RJD-led Grand Alliance in the Lok Sabha polls.
( With inputs from IANS )