India's state-run oil marketing companies have been hurt by unchanged retail pump prices for petrol and diesel for more than a year, suppressing margins and denting profits.

The company reported a net profit of 1.72 billion rupees ($20.84 million) for the quarter ended Dec. 31, compared with 8.69 billion rupees a year earlier.

Revenue from operations for the company rose 12.6% to 1.16 trillion rupees from 1.03 trillion rupees a year earlier.

Indian refiners' crude oil processing in December rose about 4% from a year earlier, provisional government data showed, in line with elevated demand in the world's third-biggest oil importer and consumer.

"During this (Oct-Dec.) period, due to the suppressed marketing margins on certain petroleum products, profitability is impacted," HPCL said in a statement, without giving additional details on those margins.

The company said its average gross refining margin - profit from converting a barrel of oil into refined products - was $11.40 per barrel for April-December, compared with $4.50 per barrel in the same period a year earlier.

Indian oil marketing company Bharat Petroleum Corp reported a 31% fall in quarterly profit, while Indian Oil Corp Ltd, the country's top refiner, posted a 92.4% fall, also hurt by static pump prices.

($1 = 82.5310 Indian rupees)

(Reporting by Nallur Sethuraman in Bengaluru; Editing by Nivedita Bhattacharjee)