The number of U.S. workers signing up for first-time jobless benefits fell to a seasonally adjusted 308,000 last week, slightly lower than expected, a government report Thursday showed.

First-time jobless claims fell by 12,000 in the week ended July 7 from the prior week's upwardly revised 320,000, according to the Labor Department report. Economists were expecting claims to inch down to 315,000 from the previously reported 318,000 claims.

U.S. Treasury debt prices turned flat after the lower-than-expected weekly jobless claims data.

A Labor Department official said that temporary layoffs in the auto sector as plants typically shut down for retooling have started to show up in the unadjusted claims data, but that the department's seasonal factors have adjusted for this.

Economists were expecting to see some volatility in this report, which is typical at this time of year.

"We are maintaining little hope that they will provide useful insight toward our July nonfarm payroll forecast," said Joe LaVorgna, chief U.S. economist at Deutsche Bank in New York.

"Initial claims are notoriously volatile in the month of July," he added.

The four-week moving average, a more reliable measure of employment conditions because it irons out weekly fluctuations, fell to 317,750 from 319,250. The number of workers remaining on jobless benefits inched down by just 4,000 to 2.554 million for the week ended June 30, the most recent week these figures were available.