Korean Air Lines Co., South Korea\'s top air carrier, said its net loss sharply widened in the second quarter of 2013 from a year earlier due to foreign exchange loss. The carrier said its foreign exchange loss stood at 261 billion won (US$233 million) for the April-June period due to the Korean won\'s decline against the U.S. dollar. The won fell 3.9 percent against the U.S. dollar in the second quarter from three months earlier, while the Korean currency rose 2.3 percent against the Japanese yen. Consolidated net loss widened to 358.7 billion won in the three months through June 30, from 164.6 billion won loss a year earlier, the Seoul-based carrier said in a regulatory filing. The airline said it posted an operating loss of 50.8 billion won, a sharp decline from a 94.4 billion won operating profit a year earlier. Sales also dipped 9.8 percent on-year to 2.8 trillion won as tensions on the Korean Peninsula led to a sharp decline of overseas demand. North Korea threatened to attack South Korea and the United States with nuclear weapons earlier in the year, though it has later toned down its harsh rhetoric and held several round of talks with South Korea meant to reopen their shared factory park in the North.