Initial claims for unemployment benefits increased by 1,000 last week to 427,000, the U.S. Labor Department said Thursday.

The four-week average of jobless claims, regarded as a more reliable guide to future trends, dipped by 2,750 to 424,000.

The official unemployment rate climbed to 9.1 percent last month as only 54,000 net new jobs were created. Most analysts had forecast a gain of between 150,000 and 170,000 positions.

During the week that ended May 28, the number of people receiving state unemployment benefits fell 71,000 to 3.68 million, the lowest level in a month.

Nearly 4 million other people continued to collect payments under special federal programs adopted to cope with the country's worst economic downturn since the Great Depression.

More than 8.4 million U.S. jobs were destroyed during the recession that began in December 2007 and ended - officially - in June 2009.

Although gross domestic product has grown over the past two years, nearly 14 million people remain out of work.

The higher U6 unemployment rate, which includes part-time workers who would prefer full-time jobs and people who have given up looking, fell slightly last month to 15.8 percent.