Patna, April 11 -- Bihar CM Nitish Kumar on Friday took the oath as Rajya Sabha member to achieve a rare distinction of being a member of four Houses. He has already served as member of the Lok Sabha, Bihar Legislative Assembly and Bihar Legislative Council. This also marks a significant transition for him from Bihar state politics to national politics after over two decades, paving the way for the formation of a new government after April 13, as JD(U) leaders have been reiterating. He returned to Patna in the evening along with Rajya Sabha MP Sanjay Jha and Bihar's Parliamentary affairs minister Vijay Kumar Choudhary and is expected to resign as CM in the coming days, but there is still no clarity on date. Talking to media persons on his return to Patna, Choudhary said that the new government would be formed after resignation of the CM. "Wait for the formation of the new government. Before swearing in, resignation has to take place. Nitish Kumar has taken oath as Rajya Sabha member, but the new government cannot be formed with that. That will require his resignation and wait till that happens," he added, indicating that the date was still not clear about the formation of the next government. Sources said that the BJP candidate for the CM post would be decided by the NDA Legislature Party leader and the brainstorming over it was still on. Rajya Sabha Chairman, Vice-President CP Radhakrishnan administered the oath in his chamber in the prese Union ministers JP Nadda, Nirmala Sitharaman, Arjun Ram Meghwal, Rajiv Ranjan alias Lalan Singh, Rajya Sabha member and JD-U working president Sanjay Jha, Rajya Sabha MP Jairam Ramesh, Lok Sabha MP Rajiv Pratap Rudy and Bitish Kumar's Bihar cabinet colleagues. Soon after the oath, Prime Minister Narendra Modi congratulated him. "Nitish Kumar is one of the nation's most experienced leaders whose commitment to good governance and indelible contribution to Bihar's development are widely recognised," he said. He further noted: "It is a pleasure to see him return to Parliament. He has also served for many years as a Member of Parliament and Union Minister. I am fully confident that his long political experience will further enhance the dignity of Parliament. Heartiest congratulations to him on taking oath as a Rajya Sabha MP, and heaps of best wishes for his upcoming term," PM Modi posted on X. Greetings for Kumar poured in from several NDA leaders for his new innings as member of the Upper House. The move to the Rajya Sabha marks the fulfilment of Kumar's long-stated desire to serve in every legislative house in India. Last month, Nitish himself posted on X that he wanted to go to Rajya Sabha, the only House he has not been a member of and that it was his decision. Kumar resigned from his membership of the Bihar Legislative Council on March 30 following his election to the upper house of Parliament on March 16 to make it clear that he was on way to handing over the reins of the Bihar government to the BJP, marking a significant structural shift in the state's power dynamics ahead of future elections. For the first time, Bihar will have a CM from the BJP, the largest party in the state Assembly. After his election to Rajya Sabha, Kumar, who has taken oath as Bihar CM for a record 10 times and been the longest serving CM of the state, was elected JD(U) president unopposed after no other candidate filed a nomination for the post. Kumar's political journey spans over four decades, starting with his first election to the Bihar Legislative Assembly in 1985 from Harnaut. Barely four years later in 1989, he entered the Lok Sabha from erstwhile Barh constituency and was appointed minister of state in the VP Singh Government in 1990. In 1994, he co-founded the Samata Party, which formed an alliance with the BJP two years later. Later, Samata Party merged into JD(U) in 2003 to fight against the misrule of the RJD and ultimately achieved the objective in 2005 as part of the NDA....