The crude oil refiner reported a net loss of 1.88 billion rupees ($23.1 million) for the quarter ended Dec. 31, compared with a profit of 5.86 billion rupees a year earlier.
The government levied a windfall tax on exports of gasoline, diesel and aviation fuels midway through last year, which, MRPL said, hits its results by 20.46 billion rupees in the quarter.
MRPL, a subsidiary of the government-owned Oil and Natural Gas Corp Ltd, said its cost of materials consumed surged 32.2% to 244.95 billion rupees.
Its throughput rose to 4.48 million metric tonnes (MMT) from 4.35 MMT. Revenue from operations increased nearly 24% to 309.66 billion rupees.
MRPL's shares have gained 2.6% so far this month, following a roughly 5.5% drop in the last quarter of 2022.
($1 = 81.4910 Indian rupees)
(Reporting by Meenakshi Maidas in Bengaluru; Editing by Savio D'Souza)