Northwest Airlines posted a wider quarterly loss on Wednesday as high fuel prices and low revenue weakened the industry.

Northwest, the No. 4 US carrier, said that excluding unusual items, its fourth-quarter loss amounted to USD$359 million. A year earlier, it posted a loss of USD$129 million.

"Stubbornly high fuel costs, revenue pressures from competitors' pricing actions and labor cost savings realized by some of our major competitors make it imperative that Northwest achieve labor restructuring quickly in order to return to profitability," chief executive Doug Steenland said in a statement.

The carrier said that it realized a net loss of USD$420 million for the fourth quarter, including unusual items.

Northwest said it ended the fourth quarter with a cash balance of USD$2.61 billion, of which USD$2.46 million was unrestricted.