Truck and engine maker Navistar International Corp. reported a bigger quarterly loss due to lower sales to the U.S. military and its transition to a new emission technology.

The company has lost market share since 2012 when U.S. regulators denied approval of a redesigned diesel engine that failed to reduce green house gas levels.

The company has had to turn to rival Cummins Inc. to supply engines as it develops its own catalytic reduction engines to reduce nitrogen oxide emissions.

"We have more hard work to do to rebuild our market share," Chief Executive Troy Clarke said in a statement on Wednesday.

Navistar has also been hurt by lower demand from the U.S. military as the government cuts spending.

The company said in December it expected its performance to pick up from the February-April quarter after the U.S. Senate passed a budget deal to ease spending cuts.

Navistar's net loss widened to $248 million, or $3.05 per share, in the first quarter ended Jan. 31 from $123 million, or $1.53 per share, a year earlier.

Revenue dropped about 16 percent to $2.21 billion.

Navistar shares closed at $37.79 on the New York Stock Exchange on Tuesday. They have fallen 1.5 percent in the past three months, underperforming an 11 percent rise in the S&P 500 index.