MUMBAI: Indian energy conglomerate Reliance Industries Ltd posted a flat quarterly profit, in line with estimates, hurt by a slimmer margin in its oil refining business.

Reliance, which operates the world's biggest refining complex in western India, said net profit for its fourth quarter ended March 31 rose to 56.31 billion rupees from 55.89 billion rupees a year earlier.

Analysts on average expected a net profit of 56.62 billion rupees, according to Thomson Reuters I/B/E/S.

Average gross refining margin (GRM) dropped to $9.3 per barrel from $10.1 a year earlier.