MRPL already holds 3% interest in OMPL, which is a joint venture with Oil and Natural Gas (ONGC).

Press Trust of India (PTI) cited MRPL as saying in a regulatory filing: "MRPL was holding 3 per cent of the paid up equity of OMPL, which has been increased to 46 per cent by purchasing fully paid up equity shares from individual shareholders."

OMPL will be 46% owned by ONGC while the remaining 8% is due to be allotted.

In a separate regulatory filing, ONGC said: "Consequent upon the approval of the Board of Directors of MRPL (a subsidiary of ONGC) in its 193rd meeting held on February 9, 2015, MRPL has acquired 43 per cent stake in OMPL by way of purchase of fully paid up equity shares from individual shareholders, resulting in increase of its holding from 3 per cent to 46 per cent of the paid up share capital of OMPL."