WASHINGTON - The number of U.S. workers filing new applications for unemployment insurance fell slightly less than expected last week, government data showed on Thursday, implying only a gradual labor market improvement.

Initial claims for state unemployment benefits dropped 11,000 to a seasonally adjusted 448,000 in the week ended April 24, the Labor Department said.

Analysts polled by Reuters had expected claims to fall to 445,000 from the previously reported 456,000, which was modestly revised up to 459,000 in Thursday's report.

Claims are still hovering at that tipping point around 450,000, which we think is the junction between corporate hiring and continuing a wait-and-see process, said Alan Gayle, senior investment strategist at Ridgeworth Investments in Richmond, Virginia. The report is moving in the right direction but is inconclusive.

U.S. index stock futures held gains after the data, while Treasury debt prices were flat. The U.S. dollar hovered at lower levels against the euro.

The four-week moving average of new claims, which irons out week-to-week volatility, rose 1,500 to 462,500, increasing for a fourth straight week.

Though initial claims have resumed their downward trend interrupted by the Easter holiday, analysts worry the pace is too slow and underscores the fragility of private hiring.

The Federal Reserve on Wednesday acknowledged the labor market was improving, but noted that employers remained reluctant to add payrolls. The U.S. central bank left overnight benchmark lending rates near zero and renewed its commitment to keep them low for an extended period.

Private hiring last month handed the economy its largest jobs gain in three years. Even with both jobless claims and the four-week average still perched above 400,000, employers are believed to have added jobs this month.

The number of people still receiving benefits after an initial week of aid fell 18,000 to 4.65 million in the week ended April 17, the Labor Department said. This was a touch above market expectations for 4.62 million.

The so-called continuing claims data covered the household survey week from which the national unemployment rate is derived. Analysts anticipate data will show the unemployment rate was unchanged at 9.7 percent in April.

The insured unemployment rate, which measures the percentage of the insured labor force that is jobless, was unchanged at 3.6 percent in the week ended April 17, the Labor Department said.

Separately, the Chicago Federal Reserve national activity index rose in March, but still indicated below-trend growth.

(Reporting by Lucia Mutikani; Additional reporting by Ann Saphir in Chicago and Ryan Vlastelica in New York; Editing by Andrea Ricci)

Unemployment