Bihar Chief Minister Nitish Kumar on Thursday said that he has sought an appointment with Prime Minister Narendra Modi to discuss the tricky issue of caste-based census which the Centre has proposed to hold only for SCs and STs, triggering protests in the state.

The Union government had informed the Parliament last month that a headcount of only the Scheduled Castes and Scheduled Tribes was proposed. This has led to renewed demands that the population of all castes be ascertained afresh in course of the census.

"My letter to the PM has been dispatched. Once he gives an appointment we will take the matter forward", the chief minister told reporters here.

Notably, the state legislature has on two occasions passed unanimous resolutions favouring a caste-based census. Moreover, leader of the opposition Tejashwi Yadav had met the chief minister last week with the suggestion that since unanimity prevailed among all political parties in Bihar over the issue of caste-based census, Kumar consider meeting the PM heading an all-party delegation.

The chief minister has also said that in the event of the Centre not agreeing to the request for covering all castes in the census, his government will "keep the option open" of conducting a state-specific exercise.

Kumar is the de facto leader of the JD(U), which has been alliance partner of the BJP for close to three decades. He holds the view that a caste-based census will help better formulation and implementation of schemes aimed at targeted welfare of different social groups.

The last time a caste-based headcount was taken up in the country was in 1931.

The Bihar CM, who had recently caused a flutter by advocating an investigation into the Pegasus controversy, expressed satisfaction over the fact that the Supreme Court was seized of the matter and making needful intervention.

"Nobody should have a problem with this. If some people feel their privacy has been violated, what better thing than to have the Apex Court looking into the matter", said Kumar when asked about the phone-tapping with the help of Pegasus spyware.

The chief minister, who was talking to journalists upon returning to the city after conducting aerial survey for flood of four districts, laughed off a query about his arch rival Lalu Prasad, who is away in Delhi, becoming "politically active".

"Let us not talk about these things. Everybody has a right to act as per his wishes", said the JD(U) leader as a parting remark.

Prasad has been recuperating in the national capital following his release from a Ranchi jail where he had been lodged upon conviction in a number of fodder scam cases.

One of the most flamboyant and colourful political personalities of his generation, Prasad has been making headlines following his recent meetings with veteran socialists like Mulayam Singh Yadav and Sharad Yadav and his advocacy of a "third front".