Neptune Orient Lines, Southeast Asia’s largest container carrier, said “significant losses” will probably continue through at least the first half of 2010 on slower world trade and a supply glut.

“Container-shipping freight rates remain at uneconomic levels,” Chief Executive Officer Ron Widdows said in a statement yesterday as the company posted its fourth quarterly loss in a row. China Cosco Holdings Co., operator of China’s largest container line, also reported a fourth straight loss.