Bathinda, INDIA -(Dow Jones)- HPCL Mittal Energy Ltd. may double capacity of its north India refinery, billionaire steel tycoon Lakshmi Niwas Mittal said Saturday.

"We may double the capacity to 360,000 barrels a day," Mittal said at an event where Prime Minister Manmohan Singh formally inaugurated the refinery.

Mumbai-based Hindustan Petroleum Corp. Ltd. (500104.BY) and Singapore's Mittal Energy Investment Pte. Ltd. each have a 49% stake in HPCL-Mittal Energy Ltd., which built the 180,000-barrel-a-day refinery at Bathinda in Punjab province, at a cost of $4 billion. Financial institutions hold the remaining 2%.

-By Rakesh Sharma; Dow Jones Newswires; 91 22 6145 6119; Gurdev.Singh@dowjones.com