* Fiber ekes out daily gain, supported by exports
* Noncommercial dealers slash long positions -CFTC
* Prices down 11 pct since August peak
NEW YORK, Sept 6 (Reuters) - Cotton futures gained on Friday for the first time in four sessions as weekly U.S. export data reinforced hope that low prices have renewed demand, although for the week the futures posted their third straight weekly loss.
The most-active December cotton contract on ICE Futures U.S. edged up 0.91 cent, or 1.1 percent, to settle at 83.21 cents per lb, the contract's biggest gain in three weeks.
The day's gains were not enough to prevent the fiber from posting its third straight down week. Prices are down more than 11 percent from a five-month high set three weeks ago, plunging as a speculator-driven rally ground to a halt.
Speculators again cut their bullish stance in cotton futures and options in the week ended Sept. 3, Commodity Futures Trading Commission (CFTC) data showed on Friday.
Noncommercial dealers have nearly halved their bullish position in fiber in the last two reporting weeks from their largest bullish position since March, data compiled by Reuters show.
Weekly U.S. government export data showed that sales to China, the world's top textile market, increased in the week ended Aug. 29 from the previous reporting period, as a steep drop in prices stirred physical demand.
"The export numbers helped provide a boost, and we're bouncing off the bottom of our trading range," said Sterling Smith, a futures specialist with Citigroup in Chicago.
The second-month contract hit a three-month low on Thursday.
While the steep fall since mid-August has prompted mill buying, U.S. cotton remains expensive relative to other origins and may limit demand, traders said.
A monthly supply and demand report is due from the U.S. government next week and there may be revisions to production forecasts, dealers said. A larger-than-expected drop in last month's forecast fueled a price rally.
Bumper output is expected in India, the world's second largest producer, and will likely keep a lid on prices, dealers said.
Dealers also will be looking at projections for China's imports, where a government stockpiling program launched in 2011 has prompted voracious demand for fiber.
Earlier this week, the USDA attache in China raised expectations for cotton imports.
Beijing is prepared to scrap the controversial program next year, Reuters reported last week. (Reporting by Chris Prentice; Editing by Bob Burgdorfer)
