The number of people filing new claims for jobless benefits jumped unexpectedly last week after three straight declines, another sign that hiring remains weak.

Initial claims for jobless benefits rose by 12,000 to a seasonally adjusted 472,000, the Labor Department said Thursday. It was the highest level in a month.

First-time claims have hovered near 450,000 since the beginning of the year after falling steadily in the second half of 2009. That has raised concerns that hiring is lackluster and could slow the recovery. Economists say they will feel more optimistic that the economy is creating jobs once initial claims fall below 425,000 per week.

The four-week average for unemployment claims, which smooths volatility, dipped slightly to 463,500. That's down by 3,750 from the start of January.

The number of people continuing to claim benefits rose by 88,000 to 4.57 million. That doesn't include about 5.2 million people who receive extended benefits paid for by the federal government.

Congress has added 73 weeks of extra benefits on top of the 26 weeks typically provided by states. All told, about 9.7 million people received unemployment insurance in the week ending May 29, the most recent data available.

The extended benefit program expired this month. Congress is debating whether to continue it through the end of November.

Adding to worries about the job market, the Labor Department said earlier this month that the economy generated only 41,000 private-sector jobs in May. That was down from 218,000 in April.

Temporary hiring by the Census Bureau added another 411,000 jobs. The unemployment rate fell to 9.7 percent from 9.9 percent.