The United States is on the verge of listing the African elephant as an endangered species and banning ivory imports, Interior Department sources said yesterday.

Pressed by conservationists and a congressional committee. Interior officials are gathering scientific data to support official protection of the world's largest land animal, which is being killed across the African continent to satisfy the international ivory market.

Testifying before the House Merchant Marine and Fisheries Committee yesterday, Assistant Interior Secretary Robert Herbst said a decision on the listing would be made within three weeks. Although he declined to say what that decision will be, other officials predicted the elephant will be listed as an endangered species.

"The African elephant [is] one of the most magnificient of all land mammals and a symbol of the freedom, strength and majesty of the wild world," Herbst told the committee, which is considering a bill to ban ivory impacts if Interior doesn't act.

Five states have outlawed the sale of imported ivory, most of the which arrives as jewelry and carved figuries. U.S. ivory imports - amounting to $3.2 million last year - account for a quarter of the world market.

Conservationists hope that an embargo would discourage illegal poaching, which accounts for the killing of 100,000 to 400,000 elephants a year.

However, Stanley W. Smith of the American Ivory Importers Association said a ban would eliminate Africans' economic incentive to preserve elephants. "Unless the elephant is bringing in money, they're going to get rid of it," he said, adding that a ban would have little effect since U.S. imports could be absorbed by other nations.

Elephants also are threatened by Africa's human population explosion. An elephant eats up to 500 pounds of vegetation a day. Many are starving or being shot as nuisances while agrilcultural and commercial development encroach on their rangeland.

Roughly 1.3 million elephants survive in Africa today, according to Dr. Iain Douglas-Hamilton, one of the world's experts on the subject, who flew here from Kenya to address the committee. He estimated that elephant populations are declining in all but four of the 33 African countries where they still exist.

Douglas-Hamilton gathers data from scientists, wardens, government officials, hunters, missionaries and farmers across the continent who find elephants killed with guns, wire snares and poison darts. Reports from Chad revealed that the army fired rockets from helicopters to kill elephants for ivory.

In Sudan, tribesman are reportedly burning the animals to death by setting fire to the grass around a herd, Douglas-Hamilton said.He attributed increased poaching to a tenfold increase in the price of ivory - to between $30 and $150 a kilo - since the late 1960s.

While some African nations prohibit the killing of elephants, enforcement has been ineffective, and in some countries, including Kenya and Uganda, government officials reportedly have been involved in the ivory trade, according to Rep. John M. Murphy (D-N.Y.).

"Ivory privides profits that are able to support bribery on a scale-that is only rivaled by the narcotics trade." Douglas-Hamilton said. He estimated that Kenya has lost more than half of its elephants since 1970, leaving about 75,000. Uganda has shown "catasrophic decline," he said.

However, Kenya has recently tried to crack down on poaching, and earlier this week it banned ivory and trophy sales within its borders. John P. Mbogua, Kenya's ambassador to Washington, said yesterday that a U.S. ban would be "most welcome."

Listing the elephant as endangered here was proposed in August by the Fund for Animals, a conversation group, which cited scientific reports that remaining herds could be destroyed in five to 10 years.