Airline operator United Continental Holdings (UAL) cited the rough winter across much of the U.S. for first-quarter losses that exceeded those from a year ago.

United said in a statement that cold weather and repeated storms widened the company’s losses in the quarter by $200 million.

The Chicago-based airline, formed in the 2010 merger between United and Continental Airlines, reported a loss of $489 million, or $1.33 a share, excluding a handful of one-time items, versus a loss of $358 million, or $1.08, a year earlier.

The most recent loss was slightly less than the $1.36 loss Wall Street analysts had predicted.

United’s shares were down 5.32% at $43.61 in morning trading.

“This quarter's financial performance is well below what we can and should achieve. We are taking the appropriate steps with our operations, network, service and product to deliver significantly better financial results,” CEO Jeff Smisek said in a statement.

United’s hubs in Chicago and Newark were particularly hard hit by the severe winter, with repeated snow storms and record-breaking cold weather forcing cancellations and delays.

Total first-quarter revenue was $8.7 billion, down 0.3% year-over-year. Consolidated revenue passenger miles and consolidated available seat miles each decreased 0.3% year-over-year for the first quarter, primarily due to the weather, which resulted in a first-quarter consolidated load factor of 81.1%.

"We recognize that we have lagged on revenue and are taking the necessary actions to remedy that," said Jim Compton, UAL's vice chairman and chief revenue officer.

Total operating expenses rose $60 million, or 0.7%, in the first quarter against the same period in 2013. Excluding special charges, first-quarter total operating expenses increased $100 million, or 1.1%, year-over-year.

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