Updated

WASHINGTON -- New jobless claims in the U.S. jumped last week by the most since February, reversing a sharp fall two weeks ago. The rise is partly a result of seasonal factors but also reflects the job market's weakness.

The Labor Department says new claims for unemployment insurance jumped by 37,000 to a seasonally adjusted 464,000. Analysts expected a smaller rise, according to a survey by Thomson Reuters.

The sharp increase comes after claims fell steeply two weeks ago to their lowest level since August 2008. But much of that drop was driven by temporary seasonal factors and not necessarily by an improving job market.

Two weeks ago, General Motors and other manufacturers reported fewer temporary layoffs than usual this time of year, the Labor Department says.