Before leaving for New Delhi, Kumar told media that the Centre should also frame new criteria for granting special status to states.
"We are making a just demand and it should be considered by the new expert committee," he said.
Kumar said "There is sufficient base for meeting Bihar's demand for special state status - a demand of the common people of the state."
He said signatures of more than 1.5 crore people in support of the demand had already been submitted to the Centre.
"We had accepted that the committee which was previously looking into the demand will make the recommendations keeping in mind the poverty and backwardness," Kumar said.
The chief minister said the talks over the issue with the Centre would not be closed and "we will continue our fight to achieve the special state category."
If the Centre didn't concede to the demand soon, "we will chalk out programme by taking people from Patna to Delhi," Kumar said.
He said he would soon write a letter to Prime Minister Manmohan Singh to press for granting special status to state.
In a major blow to Bihar government's efforts, an inter-ministerial group of Centre had rejected Bihar's demand for special status.
The group was constituted to look into the demand of the state.
