The number of people seeking U.S. unemployment benefits fell unexpectedly to a new three-month low last week, suggesting a strengthening in labor-market conditions after a winter slump, the government reported Thursday. The Labor Department said initial jobless claims fell 9,000 to 315,000 last week, the lowest reading since late November. The four-week moving average of claims, considered a better measure of conditions because it smoothes weekly volatility, fell 6,250 to 330,500, the lowest level since early December. The total number of people receiving unemployment benefits fell 48,000 to 2.86 million last week, the lowest level since December. Recent declines in jobless claims, which measure layoffs, indicate companies are confident enough about the economy to maintain their staffing levels. Employers also are hiring more after severe winter weather reduced job gains in January and December.