Korea National Oil Corp. shifted to an operating profit in the first half on high oil prices and cost-cutting efforts, the state-run utility said Thursday.

The KNOC swung to an operating profit of $55 million in the January-June period from an operating loss of $187 million a year earlier, the company said in a statement.

"The turnaround was helped by an increase in international oil prices and an adoption of stricter working processes to cut costs," the statement said.

Brent oil prices jumped by $11.8 per barrel in the first six months compared to a year earlier, though the KNOC suffered a 17 percent decline in domestic sales of oil during the same period, the company said.

Sales fell 19 percent year-over-year to $899 million in the first half from $918 million, it said. (Yonhap)