WASHINGTON - American women may know by the end of the year if they can buy the French abortion drug RU-486.

The Food and Drug Administration confirmed yesterday that the nonprofit Population Council filed an application last month seeking to sell RU-486, based on its results of testing in 2,100 American women.

FDA Commissioner David Kessler told Congress last year it would take about six months to determine if RU-486 is safe enough, and effective enough, to sell to Americans. However, the review could take up to a year, the time the agency typically spends on drugs that don't address life-threatening diseases.

The FDA is expected to approve the drug, based partly on records of its use on 150,000 European women, where it had about a 97 percent success rate.

But the U.S. testing also would have to show the drug worked. The Population Council would not release those results Monday, because it is awaiting publication of the data in a medical journal.

Almost all of the nation's 1.3 million abortions are surgical, although doctors last year began publicizing the fact that a drug already on the market to treat cancer - methotrexate - also can be used to induce abortion.

But RU-486, known chemically as mifepristone, would be the first drug specifically approved by the FDA for non-surgical abortion.

''The FDA should not be approving a drug whose sole intention is to kill,'' said Gracie Hsu of the Family Research Council, which opposes abortion.

Pressure from abortion opponents prompted French manufacturer Roussel Uclaf to refuse for years to bring RU-486 to this country. Last year, the Clinton administration brokered a deal giving the Population Council the U.S. patent rights to the drug, so it could seek FDA approval.

RU-486 blocks development of progesterone, a natural steroid hormone that is essential for maintaining pregnancy. A doctor administers the pill and two days later gives the woman a prostaglandin, a hormone that causes contractions to expel the embryo.

The process can be painful and, because it takes several days, many European women have opted for surgical abortions. Like surgical abortions, there can be side effects, including heavy bleeding and nausea, and it can be used only through the seventh week of pregnancy.

Because of the risks, federal health officials have said RU-486 won't be an over-the-counter remedy, and should be administered only by specially trained doctors.

The methotrexate that some doctors already use for non-surgical abortions also requires a return trip for a prostaglandin, but it takes about a week instead of two days.

Preparing for the FDA's possible approval of RU-486, the Population Council has given exclusive legal rights to a new company in Washington, Advances in Health Technology, to coordinate the drug's manufacture and distribution.

The council refused to name the actual manufacturer because of security concerns, and federal regulations allow the FDA to keep the identity secret.

RU-486 also has been considered as a possible treatment for breast cancer and as a ''morning after'' pill to prevent pregnancy, and enough will be produced for scientists to research those uses, said council spokeswoman Sandra Waldman.