June 19 (Bloomberg) -- Cotton for December delivery rose, heading for the longest rally since March, as demand for supplies before this yearΆs harvest bolstered forward prices.

The cotton contract for July delivery surged the most allowed by ICE Futures U.S., trading more than 13 cents a pound above the price for December. That compared with 1 cent on June 1. In the week ended June 7, U.S. export sales of the so-called old crop soared fivefold from a week earlier, government data showed on June 14.

“The export number last week was huge, and July futures continue to trade up,” Scott Joss, the president of ClearTrade Commodities, a broker in Chicago, said in a telephone interview. “Someone is going to take delivery, and the shorts are trapped. ThatΆs dragging the December contract along.”

On ICE in New York, cotton futures for December delivery, the contract with the highest open interest, rose 3.3 percent to 74.26 cents at 11:02 a.m. That price climbed for the fifth straight session, heading for the longest rally since late March.

Cotton futures for July delivery jumped by the limit of 5 cents, or a record 6 percent, to 87.98 cents, the highest since May 7. The first day for traders to notify counterparties on whether they intend to take delivery is June 25.

Federal Reserve policy makers start a two-day meeting today on the outlook for the U.S. economy, and the central bank is scheduled to issue a statement tomorrow.

“Everybody is still hopeful that the Fed will indicate some sort of monetary easing” to bolster the slowing economy, Joss said.