New claims for unemployment benefits rose more than expected last week, a government report showed on Thursday, but the underlying trend continued to point to improving labor market conditions.

Initial claims for state unemployment benefits increased 15,000 to a seasonally adjusted 381,000, the Labor Department said. The prior week's claims data was revised up to 366,000 from the previously reported 364,000.

Economists polled by Reuters had forecast claims rising to 375,000. A Labor Department official said that because of a public holiday on Monday, claims from seven states - including California and Virginia - had been estimated.

The four-week moving average - a better measure of trends - fell 5,750 to 375,000, the lowest level since June 2008.

We've seen a pretty strong trend in claims recently. This finally shows they're correcting to a sustainable downtrend, said Gennadiy Goldberg, interest-rate strategist at 4CAST in New York.

U.S. stock index futures added modestly to gains, while prices for government debt were little changed. The dollar was up against the euro.

While the rise in initial claims last week interrupted three straight weeks of declines, the healing in the jobs market remains intact.

Claims remain below the 400,000 mark that is normally associated with an improvement in labor market conditions.

The better tone should feed into consumer spending, which slowed significantly in November, and support economic growth.

Already, firming employment -- marked by a drop in the jobless rate to a 2-1/2 year low of 8.6 percent in November -- is helping to buoy consumer confidence.

While much of the global economy is slowing and the debt crisis in Europe is expected to push the region into a mild recession next year, output in the United States has held up relatively well.

Fourth-quarter growth is expected to top a 3.0 percent annual pace, quickening from the July-September period's 1.8 percent rate. The economy's resilience, however, could be tested next year if the euro zone situation worsens.

The claims data showed the number of people still receiving benefits under regular state programs after an initial week of aid rose 34,000 to 3.60 million in the week ended December 17.

Economists had forecast so-called continuing claims rising to 3.56 million from a previously reported 3.55 million.

The number of Americans on emergency unemployment benefits fell 15,022 to 2.93 million in the week ended December 10, the latest week for which data is available.

A total of 7.23 million people were claiming unemployment benefits during that period under all programs, up 79,385 from the prior week.

(Reporting by Lucia Mutikani; Editing by Chizu Nomiyama)