TREASURIES-U.S. yields fall on dovish Bank of England, soft data

* U.S. yields fall with tumbling UK bond yields

* ISM non-manufacturing index weakens

* Treasury yield curve flattest in a week

* Report on Mueller convening a grand jury spurs late buying

(Adds report on Mueller impaneling grand jury) NEW YORK, Aug 3 (Reuters) - U.S. Treasury yields fell to more than one-week lows on Thursday after the Bank of England kept interest rates at a record low and downgraded its economic and inflation forecasts, raising concerns about global economic growth. Investors had begun to price in the chance that the BoE might raise interest rates this month for the first time in a decade. Thursdays decision sent yields on 10-year UK government debt tumbling to their lowest since June 28. "It's pretty dovish testimony. They are again walking back policy," said Tom di Galoma, a managing director at Seaport Global Holdings in New York. Weak U.S. non-manufacturing data also boosted bonds. The Institute for Supply Management (ISM) said its non-manufacturing index fell to a reading of 53.9 last month from 57.4 in June. A reading above 50 indicates an expansion in the services sector, which accounts for more than two-thirds of the U.S. economy. A late flurry of safe-haven buying emerged after The Wall Street Journal reported that special counsel Robert Mueller has convened a grand jury in the probe into Russia's alleged interference in the 2016 U.S. elections. U.S. benchmark 10-year Treasury notes gained 10/32 in price to yield 2.225 percent, down from 2.262 percent late on Wednesday. The yield on benchmark notes touched 2.218 percent, the lowest since June 29, after the grand jury report. Friday's employment report for July is this week's main economic focus. Employers are expected to have added 183,000 jobs in the month, according to the median estimate of 92 economists polled by Reuters. The Treasury yield curve also continued to flatten, a day after the U.S. Treasury Department said it was still considering an ultra long bond but did not announce a new issue. The Treasury gave no timing for when it may make a decision on the bond. It also said it has begun to consider how it will increase debt issuance to make up for a future decline in U.S. Federal Reserve bond purchases. The yield curve between five-year notes and 30-year bonds flattened to 101 basis points, the lowest since July 25. Large block trades in bond futures contracts may have helped boost the long-dated debt. A block of 7,453 contracts was purchased on Treasury bond futures at 7:37 a.m. EDT (1137 GMT) on Thursday, after a block of 7,483 contracts was bought at 8:52 a.m. EDT on Wednesday, according to data by the CME Group.

Thursday, Aug. 3, at 1616 EDT (2016 GMT): Price

US T BONDS SEP7 155-5/32 0-30/32 10YR TNotes SEP7 126-100/256 0-72/256 Price Current Net Yield Change (pct) (bps) Three-month bills 1.0675 1.0852 0.007 Six-month bills 1.1225 1.1445 0.000 Two-year note 100-16/256 1.343 -0.020 Three-year note 100-14/256 1.4809 -0.027 Five-year note 100-104/256 1.7895 -0.031 Seven-year note 100-132/256 2.0454 -0.037 10-year note 101-84/256 2.223 -0.039 30-year bond 104-12/256 2.7987 -0.047


Last (bps) Net

Change (bps)

U.S. 2-year dollar swap 24.25 0.25


U.S. 3-year dollar swap 21.00 0.75


U.S. 5-year dollar swap 7.75 0.75


U.S. 10-year dollar swap -3.00 1.00


U.S. 30-year dollar swap -31.50 1.25


(Additional reporting by Richard Leong, editing by G Crosse)