Singapore's Neptune Orient Lines (NOL) widened its net loss in 2014 by 241 percent to US$260 million, based on group revenues of $8.61 billion, which fell two percent year on year.

But the company that owns APL, the world's 10th largest container line, narrowed its fourth quarter loss 38 percent to $85 million, drawn on revenues of $2.22 billion, which fell five percent.

"In spite of challenging conditions, especially on the US west coast, our container shipping arm reduced its operating losses, reflecting progress in its efficiency drive," said NOL chief executive Ng Yat Chung.

APL narrowed its year-on-year loss by 64 percent to US$37 million in the fourth quarter, cutting back capacity and enhancing cargo selection.

Volume fell eight percent in the quarter year on year as a result of capacity management and fewer sailings in the transpacific services calling at southern California ports.

The seven percent year-on-year drop in fourth quarter revenue to $1.8 billion was attributed to US west coast congestion.

"Our logistics business continued to grow, expanding its capability and presence in key growth markets," said Mr Ng.

Said APL President Kenneth Glenn: "Congestion on the US West Coast due labour negotiations hampered our operational ability in the fourth quarter."

On reducing capacity to increase yields, Mr Glenn said: "We have 19 chartered ships scheduled for expiry in 2015, this will further enhance our cost structure."