Korean Air Lines Co Ltd, the world's top freight carrier among commercial airlines, reported a 41 percent drop in quarterly operating profit, hit by higher fuel costs but said it expected cargo demand to improve following the march 11 earthquake in Japan.

South Korea's No.1 airline posted made 163 billion Korean won ($153 million) in consolidated operating profit for the January-March quarter under new accounting rules, down from 277 billion won a year earlier, as fuel costs soared by 30 percent.

Net profit, however, jumped 50 percent to 282 billion won, thanks to foreign-exchange translation gains from a stronger won and solid results from its affiliates , the company said.

The South Korean flag carrier said it expected cargo traffic to improve in the current quarter, driven by post-quake demand rise and diversification efforts by global manufacturers to secure components and raw materials outside quake-hit Japanese suppliers.

" Concerns over a drop-off in travel demand after Japan's earthquake are easing with prospects over the global economic recovery," said Jung Yun-jin, an analyst at Kyobo Securities.

Korean Air said it would begin Airbus A380 services from June, but take delivery of Boeing's

787 Dreamliners in 2016, five years later than initially planned to 2016 . (Reuters)