The number of U.S. workers filing new claims for jobless aid unexpectedly declined by 14,000 last week, government data showed on Thursday, while continued claims notched a fresh record high as the recession chilled the labor market.

Initial claims for state unemployment insurance benefits fell to a seasonally adjusted 631,000 in the week ended April 25 from a revised 645,000 the prior week, the Labor Department said. Analysts polled by Reuters forecast 643,000 new claims versus a previously reported count of 640,000 the week before.

The severe U.S. recession has already cost over 5 million jobs since it began in late 2007. But recent indicators signal the pace of deterioration may be slowing and officials say they expect growth to gradually recover in the second half of the year, although unemployment will continue to rise into 2010.

The Labor Department said the number of people staying on the benefits roll after drawing an initial week of jobless aid rose by 133,000 to 6.271 million in the week ended April 18, the most recent week for which data is available. Analysts had estimated so-called continued claims would be 6.20 million.

It was the 13th consecutive week that continued claims have posted a record reading and this pushed the insured unemployment rate to 4.7 percent from 4.6 percent the week before, the highest reading since December 1982.

A Labor Department official said that there were no special factors impacting last week's data, with no states' claims estimated and a fairly broadly distributed pattern of reductions.

The four-week average of new jobless claims, a better gauge of underlying labor trends because it irons out week-to-week volatility, declined for the third week in a row, dropping to 637,250 from 648,000 the week before. This was the lowest reading since the end of February, when the four week average for claims was 636,750.

(Editing by Chizu Nomiyama)