Toshiba Corp. said its first-quarter net loss widened because of deteriorating earnings at its semiconductor business.

The net loss in the three months that ended June 30 increased to ¥57.8 billion, from ¥11.6 billion a year earlier, the company said Wednesday. That compares with shortfalls of ¥85 billion and ¥38.4 billion in two analyst estimates compiled by Bloomberg.

Toshiba is relying on power-generation and social-infrastructure operations, its most profitable business, to help weather a slump in demand for memory chips that forced the company to post the widest annual deficit in its 70-year history. President Norio Sasaki aims to return the company to profit on an operating basis in the 12 months ending March 31 by reducing costs by more than ¥300 billion through job and spending cuts.

Toshiba shares have climbed 11 percent this year after losing 56 percent in 2008.

The operating loss, or sales minus the cost of goods sold and administrative expenses, was ¥37.6 billion in the quarter, compared with a ¥22.9 billion deficit a year earlier, the company said. Revenue fell 17 percent to ¥1.34 trillion.

The company maintained its full-year profit and revenue forecasts.