WASHINGTON — The Sweetener Users Association has asked the U.S. Department of Agriculture for “a substantial and immediate increase” in raw and refined sugar tariff rate quotas, among other measures, to “assure adequate supplies at reasonable prices” in the United States for the remainder of 2011-12 and into early 2012-13.

The request came on the heels of the U.S.D.A. World Agricultural Supply and Demand Estimates on April 10 that projected the 2011-12 U.S. sugar ending stocks-to-use ratio at 6.8%, down from 9% projected in March and compared with 12.7% in 2010-11 and 13.2% in 2009-10. The U.S.D.A. projected the carryover of U.S. sugar on Oct. 1, 2012, at 797,000 short tons, raw value, down 24% from 1,047,000 tons projected in March and down 46% from 1,472,000 tons in 2011. The decrease resulted from a projected 385,000-ton reduction in 2011-12 sugar imports from Mexico only partially offset by a forecast 5,000-ton increase in high-tier imports and a 130,000-ton increase in U.S. beet sugar production.

Projected U.S. 2011-12 cane sugar production, domestic use and exports were unchanged from March.

“Ending stocks are now projected at just 6.8% of total use, well under half of a normal level even under the most conservative assumptions,” the S.U.A. said in the letter addressed to Michael Scuse, acting undersecretary of Farm and Foreign Agricultural Services. “Clearly, there is no case to be made for delaying a major T.R.Q. increase.”

The S.U.A. said a T.R.Q. increase of 982,000 short tons, raw value, was needed to bring the stocks-to-use ratio to the targeted 14.5%, and 1,110,000 tons was needed to attain the association’s advocated ratio of 15.5%. The S.U.A. also noted that a shortfall of about 10% in the T.R.Q. must be expected at this point in the season (sugar marketing year is October to September).

“Of the total T.R.Q. increase, we believe a substantial portion should be refined sugar, recognizing that the lost Mexican imports would have included substantial amounts of refined sugar,” the S.U.A. said. “Through February, imports from Mexico totaled 352,000 tonnes, raw value, but only 76,000 tonnes went to refiners. Last year imports from Mexico to non-reporting entities accounted for 966,000 tons of food use.”

The S.U.A. also requested the U.S.D.A. permit early entry of 2012-13 T.R.Q. sugar during the latter part of 2011-12 (ending Sept. 30, 2011), and the U.S.D.A. work with the Office of the U.S. Trade Representative to reallocate T.R.Q. amounts to reduce shortfalls.

The S.U.A. also made a request to increase the 2011-12 T.R.Q. in late March prior to April 1, the date after which the U.S.D.A. can make adjustments without restrictions. But the U.S.D.A. did not immediately adjust the T.R.Q. after April 1. Last year the U.S.D.A. announced a 325,000-ton T.R.Q. increase three days after the April 8, 2011, WASDE, raising the projected 2010-11 ending stocks-to-use ratio to 13.5% from 10.4%