The Communist Party of India-Marxist (CPI-M) on Thursday said that the proposed caste census should ensure a "scientific count" of Other Backward Classes (OBC).
Party leader Sitaram Yechury told reporters outside parliament that an OBC count would provide information about numbers of the community, which had been given reservation benefits by the government.
He said that methodology of the OBC headcount has to be decided by the government.
"The count should be done scientifically. It is for the government to decide how to do it," Yechury said.
Finance Minister Pranab Mukherjee said on Thursday that the Group of Ministers on caste-based census tasked to look into the demand had given the green signal to go ahead, but the final decision on "how and when this should be done" would be taken by the cabinet.
Mukherjee headed the ministerial panel.