Net sales and revenues for the March quarter totalled $312 million compared to $283.1 million a year ago. First-quarter revenue improvements were primarily due to higher metallurgical coke and coking coal sales volumes, which were partially offset by lower realised coking coal selling prices.

"We generated strong first-quarter 2010 results as recoveries in both the domestic and international steel industries continue," interim chief executive Joe Leonard said.

"Looking forward, Walter Energy expects to generate increased earnings for the second quarter following our recent coking coal settlements."

The company settled coking coal contracts totalling 1.7 million tonnes with prices at about $235/t free-on-board port for the six-month period beginning April 1, 2010.

"We are pleased with our coking coal contract prices for this year," Leonard said. "Coupled with record pricing on carryover tons from 2008-09 and our expanding production base, Walter Energy is positioned for an excellent year."

Operating income totalled $71.3 million for the quarter, compared to $101.5 million a year earlier, with the decline primarily due to lower coking coal pricing and higher production costs.

The underground mining segment reported net sales and revenues of $240.3 million in the first quarter 2010, compared to $244.2 million a year ago. Operating income was $64.8 million, compared to $99.9 million.

Coking coal sales volumes were up compared to last year's first quarter. However, revenues in the current period declined due to lower realized selling prices.