Chilean Foreign Minister Hernan Cubillos said Wednesday that it is still possible -- but unlikely -- that Gen. Juan Manuel Contreras Sepilveda, the former head of Chile's intelligence service, will be extradited to stand trial in the United States for the assassination of Orlando Letelier.

Cubillos said in an hour-long interview that he had no inside information and that Supreme Court President Israel Borquez -- who will decide, probably next month, whether to extradite Contreras and two other secret police officers -- is independent of Chile's military government.

"But I think you will find the general feeling is that, if the proof is sufficient, probably what will happen is that they will be processed in Chile.

"But this is no guarantee. The Supreme Court can do whatever it likes," Cubillos said. "They do not have a framework in which they have to work. Anything could happen."

Contreras, Pedro Espinoza Bravo and Armando Fernandez Larios, all current or former intelligence officers, were charged by a federal jury last summer with participating in Letelier's murder in 1976. The United States asked last September that the three be extradited to stand trial for the assassination.

Cubillos said he was aware that the Supreme Court's decision to grant or deny the extradition request could have "diplomatic and political implications" for Chile.

Nonetheless, he said, he knew of no case in which one country had given up the head or former head of its intelligence services to be tried in another country for alleged crime. Cubillos also said it was his understanding that "there have been many requests for extradition on both sides" since the United States and Chile entered into a bilateral extradition treaty more than 75 years ago.

"I have been told that there has been no case where [extradition] has been granted," because both countries have insisted on trying their own nationals, he said. "That is the way it has worked."

Cubillos is the only ranking Chilean official to conjecture publicly about the likely outcome of the extradition request.He has a reputation for speaking frankly on sensitive issues. He insisted that he knows little more about the Letelier trial in Washington -- or the evidence presented here against the three intelligence officers -- than an average Chilean would know from reading newspaper accounts.

But the foreign minister said most people here believe that Borquez will not order Contreras and the others extradicted, an observation borne out by interviews with Chileans of various political views.

The overall impression here is that federal prosecutors in Washington have little evidence linking the Letelier assassination to Contreras and his subordinates except the word of Michael Townley, who has been depicted in the press here as a ruthless killer, a liar and a double agent who committed the assassination at the behest of the CIA.

In more sophisticated circles, both supporters and opponents of the military government say they think Townley probably was working for the DINA secret police and it is even thought that the United States might have sufficient evidence to link the crime to Espinoza, Fernandez and Contreras.

But hardly any of those questioned said they believe there is any evidence linking the crime to the president, Gen. Augusto Pinochet, whose downfall as a result of the Letelier affair had been joyously awaited by opponents of the military government when the Letelier case broke open a year ago.

There could be some rough sailing in the months ahead for Pinochet -- politically and diplomatically -- as a result of the Letelier case, but even his opponents seem to think the president will not be seriously injured.

Politically, there is the possibility that Contreras, if he were put on trial, could say that Pinochet ordered the assassination. "Yes, but it would be expected," said one government supporter. "Contreras would have to prove it. Otherwise, it would be his word against the president's."

Diplomatically, if Borquez dismissed the evidence against the three Chileans and ordered them freed without a trial, the United States would probably feel compelled to retaliate, possibly by recalling Ambassador George Landau. But if the three Cubans are found not guilty in Washington, based primarily on the same evidence that the United States placed before Borquez, then a decision by Borquez to free the three probably would not result in the same diplomatic consequences.

Still, Cubillos said the whole Letelier affair has had a serious negative impact on Chile's relations with the United States, "but I hope and trust the damage won't be everlasting."