A Vedanta spokesman declined to comment.
Last May, the Cabinet Committee on Economic Affairs had approved the sale of 1,240 million shares held by the government in HZL.
The HZL and Vedanta zinc business merger is crucial for the group to meet its future financial obligations. On February 9, S&P had warned that the liquidity of Vedanta Resources, the parent firm of BSE-listed Vedanta, is dependent on its ability to raise $2 billion and on the HZL merger deal. The zinc transaction would be positive for the company, providing Vedanta Resources with potentially $2 billion of liquidity, S&P had said.