SEOUL, DEC. 2 -- The commander of U.S. forces in South Korea said today that he cannot imagine any scenario in which the United States would use nuclear weapons here.

Gen. Louis C. Menetrey, following standard U.S. policy, said that he would neither confirm nor deny the presence of nuclear weapons in South Korea. But, answering a question at a forum of Korean and U.S. military experts, he was unusually explicit in ruling out their use.

"I do not envision any circumstance which . . . would require the use of nuclear weapons," the four-star general said.

The United States is widely believed to store several hundred tactical nuclear weapons, including atomic demolition mines, well south of the Demilitarized Zone bordering North Korea. Menetrey, who assumed command here this summer, appeared to lend credibility to that belief when he said it would be "pretty dumb" to keep nuclear weapons near the DMZ, but did not address the issue of storing them farther to the rear.

In any case, Menetrey added, "tactical nuclear weapons, wherever they might be, are a deterrent."

The general's comments came at the close of a three-day conference here sponsored by the Council on U.S.-Korean Security Studies. The council is chaired by retired general Richard G. Stilwell, a former commander here and former deputy undersecretary of defense in the Reagan administration, and retired Korean general Paik Sun Yup.

The controversial issue of nuclear weapons in South Korea was raised by Peter Hayes, a member of the Energy and Resources Group at the University of California in Berkeley and a critic of U.S. nuclear policy in South Korea.

Hayes said that partly because of the presence of U.S. nuclear weapons here, there may be more danger of a conflict in Korea escalating into nuclear war than anywhere else in the world. He said the United States has deployed short-range nuclear artillery shells and nuclear mines, which are designed to impede the advance of invading armies by creating craters, closing mountain passes and otherwise rearranging the landscape.

Hayes said that such short-range weapons have little military use, because the radioactive fallout would be as dangerous to friendly forces and civilians as to the enemy. In addition, he said, such weapons would be "highly vulnerable to seizure or loss of control."

"They invite, even beg, preemption by North Koreans," he said.

The presence of nuclear weapons in South Korea is potentially volatile as an issue in the current presidential campaign, although it has not become one, as some officials feared.