TREASURIES-Safe-haven bidding boosts Treasury debt prices

* Weaker stock futures boost bonds' safe-haven allure

* Global economic worries up after S&P downgrades Britain

* Weekly U.S. jobless claims add to economic concerns

NEW YORK, May 21 - U.S. Treasury debt prices rose on Thursday as weaker stock futures boosted the safe-haven appeal of government debt amid worries that the global economy may not be recovering as quickly as originally thought.

Asian and European stocks led U.S. equity futures lower after Standard & Poor's cut its outlook on Britain to negative from stable, and investors continued to fret over a more pessimistic outlook for economic recovery from the U.S. Federal Reserve.

Weekly U.S. jobless claims on Thursday, while near economists' expectations, also offered little in the way of hope for an imminent end to the recession, with so-called continued claims rising to a fresh record.

" confirms what the Fed minutes said yesterday -- this reinforces the view that we are not out of this yet," said Lee Olver, fixed income strategist at SMH Capital in Houston.

Benchmark 10-year Treasury notes were trading 11/32 higher in price for a yield of 3.16 percent, down from 3.20 percent late on Wednesday, while the two-year note was unchanged in price for a yield of 0.84 percent.

The Fed has cut its forecast for economic growth over the next three years, although it did note there were modest improvements in the economy last month. The information was released on Wednesday in minutes from the central bank's April policy meeting.

While the number of U.S. workers filing new claims for jobless aid fell last week, the number of people staying on the benefits roll after drawing an initial week of aid rose by more than forecast to reach a record.