Updated

Patna/New Delhi, Jul 26 (IANS): In dramatic developments in Bihar, Nitish Kumar on Wednesday resigned as Chief Minister dumping the RJD and Congress to stitch a new alliance with BJP, which quickly announced support to a new government under him and said it will join it too.

Nitish Kumar, whose resignation was immediately accepted by Governor Keshari Nath Tripathi, is expected to stake claim to form the new government on Thursday in which Sushil Kumar Modi is likely to return as Deputy Chief Minister.

Ending a 20-month-long coalition of the Grand Alliance that defeated the BJP in 2015, Nitish Kumar met the Governor in the evening and handed his resignation claiming he can't work in the "current circumstances" following corruption charges against Deputy Chief Minister Tejashwi Yadav -- son of RJD chief Lalu Prasad.

But he didn't rule out a tie-up with the BJP to run a future government. As if in synchronization, Prime Minister Narendra Modi hailed Nitish Kumar's resignation, the BJP announced its support to the JD-U leader, Bihar BJP leaders had dinner with Nitish Kumar and then gave a letter of support to the Governor -- all in a matter of three hours.

"I have been doing my best to provide good governance... But the circumstances have so developed that it was difficult for a person like me to continue to be in power. That is why I met the Governor and gave my resignation," he told reporters outside Raj Bhavan.

He was initially evasive about taking support from the Bharatiya Janata Party. "What has to happen has happened. What will happen now you keep watching. We will definitely keep Bihar's interest in mind and do what is good for Bihar and its people," he said.

Nitish Kumar did not recommended the dissolution of the assembly, indicating his readiness to work with the BJP.

Shortly after Prime Minister Modi welcomed the developments in Bihar, BJP leader and former Deputy Chief Minister Sushil Kumar Modi said his party was against mid-tern polls.

"Many many congratulations to Nitish Kumar for joining the fight against corruption. 125 crore citizens of the country welcome and support this honest move," the Prime Minister tweeted.

"It is the need of the hour to rise above political differences for the bright future of Bihar and unite in the fight against corruption," he added.

Nitish Kumar responded: "I am thankful to Narendra Modi for supporting the decision I took."

The BJP Parliamentary Board quickly met in Delhi and appointed a three-member committee of Bihar leaders to study the situation.

Then Sushil Modi announced that the BJP would support Nitish Kumar to form a new government in which it would be the junior partner.

"We will support the government under the leadership of Nitish Kumar. The BJP legislature party has full confidence in Nitish Kumar as its leader. The decision has also been conveyed to Nitish Kumar which he has accepted," Sushil Modi said.

Ever since the CBI filed cases of corruption against Tejashwi Yadav, his father Lalu Prasad and sister Misa Yadav, pressure had been mounting on the Chief Minister to sack his deputy.

But any action against the Deputy Chief Minister could have evoked the wrath of the RJD, whose support was vital for Nitish Kumar.

In the 243-member assembly, the RJD has 80 MLAs, the JD-U 71 and Congress 27. The BJP has 53 MLAs and its allies LJP 2, RLSP 2 and HAM 1. There are four independents and four MLAs belong to the CPI-ML.

The JD-U and BJP together make up for 124 seats and with BJP allies the total could go up to 129, clearly crossing the half-way mark.

Nitish Kumar ran a coalition government with the BJP earlier. But he severed ties with it after it announced Narendra Modi as its Prime Ministerial candidate.

Giving reasons for his decision to quit on Wednesday, Nitish Kumar said that with a slew of corruption charges, he expected Tejashwi Yadav to give an explanation that could have formed the basis for his continuing in office.

"I waited so that we could have found a way out but nothing of the sort happened. The charges were against a member of the government. I was not in a position to do anything. There was no basis for the government to function.

"In such a situation, it was not possible for the government to function. I heeded to the call of my conscience and decided to resign."

He said he told Lalu Prasad, Congress leader C.P. Joshi and the JD-U Legislature Party about his decision to resign.

He said he faced a lot of criticism for supporting demonetisation, which had caught the people's imagination, and back Ram Nath Kovind -- "who had done a good job as Governor of Bihar and whose becoming the President was a matter of pride for the state".

RJD chief Lalu Prasad said the developments were "pre-planned" and accused Nitish Kumar of being in league with Narendra Modi and the RSS. He said Nitish Kumar resigned not because of Tejashwi Yadav but due to a murder case against him.

Lalu Prasad also suggested that the legislators of the JD-U, RJD and Congress should elect a new leader minus Nitish Kumar and Tejashwi Yadav to form a new government.