During the Vietnam war U.S. intelligence agents proposed ways of kidnaping North Vietnamese leaders, but "we couldn't even identify where the North Vietnamese lived,, much less kidnap them," a former CIA official said yesterday.

Frank Snepp, who spent five years in the Central Intelligence Agency's Saigon office, said in an interview on "60 Minutes" (CBS, WTOP) that the proposal by the CIA and the Pentagon was made in response to a request by then national security adviser Henry A. Kissinger.

Kissinger was frustrated in late 1971 and early 1972 in his Paris negotiations with Hanoi's Le Duc Thos, according to Snepp, so he asked for the intelligence contingency studies to see if there was "some way to get these negotiations off dead center."

Snepp discussed the kidnaping study, which he said was "rather amusing," in connection with the publication this week of his book, "Decent Interval." The book charges that the April, 1975, American evacuation of South Vietnam was a disaster caused by major intelligence failures by U.S. officials in Vietnam and Washington.

The CIA has charged that Snepp violated his secrecy oath and a specific promise to CIA Director Stansfield M. Turner that he would submit his manuscript to the agency for security clearance before publication.

Snepp repeated in the television interview, which was taped a month ago and released last night, what he wrote in his book: that he disregarded his oath because the CIA had made selective leaks to the press in order to "whitewash its role" in the evacuation.

In his book but not in the interview Snepp said one CIA and Pentagon proposal "called for the assassination and/or kidnaping of one or more of North Vietnam's leaders, on the theory this might precipitate such turmoil in Hanoi the survivors would be obliged to bow to U.S. demands.

Although Kissinger could not be reached for comment, "60 Minutes" interviewer Mike Wallace said he denied any knowledge of a plan to kidnap North Vietnamese leaders. "What would we done with them if we got them?" he asked, according to Wallace.

Snepp also said Kissinger's negotiations with the North Vietnamese were so secret that the CIA first learned of their progress "from our best agent inside the Communist command.

"As a matter of act, Kissinger so misled the South Vietnamese that on the very day of the cease-fire, President (Nguyen Van) Thieu didn't even have a complete copy of the Paris accord. He didn't know what Kissinger had negotiated for him," Snepp said.

Describing the chaos of the last days of the Thieu regime before the Americans left and the North Vietnamese took over, Snepp said, U.S. embassy employees in Saigon had been ordered to turn stacks of American money.

"It almost got burned up," Snepp said, "but the fellows who were to do the burning absconded with some of the funds. They took it out under the dresses of their Vietnamese girl friends." Snepp added that they took out $80,000 to $90,000.

He also said South Vietnamese officials were working to carry out $220 million in gold, the remainder of their government's national treasury. But the gold "was never evacuated," Snepp said, and one reason was that "the man who controlled it, the economics' minister in the last Saigon regime, was working for North Vietnamese intelligence."

Snepp said that Saudi Arabia's King Faisal had agreed, before he was assassinated on March 28, 1975, to provide money to help the South Vietnamese "as personal favor to Henry Kissinger."

Despite the assassination, the U.S. ambassador to Saigon, Graham A. Martin, urged Kissinger on April 17, 1975, just two weeks before the collapse of South Vietnam, to revive the idea of aid with the Saudis, Snepp said.

"As a matter of fact, the same thing was done with the Iranians," Snepp said. "We were seeking aid from the Iranians to help the South Vietnamese."

Wallace said Kissinger did talk to Faisal about financial aid and that Faisal told him South Vietnam would "get cut rates on ail the oil they needed. To the South Vietnamese that would have been worth $300,000 a year," Wallace said.

Snepp also charged tht the U.S. embassy protected top officials of the South Vietnam government from drug-dealing investigations by American narcotics agents. "The CIA, in fact, frustrated various probes into the drug problem from time to time whenever an important agent . . . was involved," he said. The CIA declined to comment yesterday.

Snepp said that when the CIA learned he was writing the book, "they called several of my colleagues in the agency in, tried to squeeze information out of them, get them to inform on me, and, infact, tried to force me to identify the publishers that I had been in touch with in my preparations for writing this book. They called in a girl I had dated in the agency, threatened to fire her unless she informed on me. But this is standard practice."

In a postscript to the interview, Wallace said Ellsworth Bunker, onetime ambassador to South Vietnam, denied a Snepp charge of having offered a $3 million bribe to Gen. Duong Van (Big) Minh if he would run against President Thieu and create the semblance of a contested election in 1971.