U.S. District Judge Manuel Real in Los Angeles ordered last December that the banks turn the money over to him to partially satisfy a $1.9 billion judgment against Marcos' estate by a federal jury in Hawaii.

Jurors found last year that Marcos was responsible for torturing and killing Filipinos. Marcos died in exile in 1989.

The Swiss threats were contained in diplomatic letters from Swiss officials that are attached to briefs lodged in the federal 9th Circuit Court of Appeals in San Francisco. The letters were reviewed by the Los Angeles Times.

Michael Andre Fels, head of the Swiss federal office for police matters, wrote that unless the Los Angeles federal judge's order is reversed it could have a ''negative effect'' on a cooperative legal assistance treaty between the two countries.

The U.S. State and Justice departments have moved to pacify the Swiss, a step condemned by the lawyer plaintiffs in a decade-old human rights lawsuit filed by 9,540 victims of the Marcos government.

''Apparently nothing is too shameful for the Swiss government in protecting Swiss banks. They're trying to intimidate the appeals court,'' said plaintiffs attorney Robert Swift.

Secretary of State Warren Christopher and Attorney General Janet Reno ''should be equally ashamed to have subjugated the compensation of human rights victims to Swiss banking interests,'' Swift said.

''We emphasize that the banks may not comply with Real's order without directly violating Swiss law,'' wrote Michael Andre Fels, head of the Swiss federal office for police matters.

''Any effort by the United States courts to enforce the order through the imposition of sanctions on the banks would conflict with Swiss sovereignty, international law and Swiss criminal law,'' he added.

The diplomatic incident means the human rights case isn't likely to be concluded soon.

The Swiss filed a legal brief stating all Marcos assets in Switzerland were frozen in 1986 and ''Swiss law does not provide discretion to lift the freeze in reaction to the order of a U.S. court.''

Philippine officials said they were trying to recover about $1.5 billion the Marcos and his wife Imelda reportedly robbed from their country and stashed in other countries, including the United States and Switzerland.

Criminal proceedings stemming from those allegations against Marcos' widow are still pending in the Philippines.

Real's order ''improperly threatens important interests of the United States, Switzerland and the Philippines,'' U.S. lawyers said in a brief urging reversal of the Real's decision.

Swift must file his reply brief by Feb. 27, and an oral argument is expected to be held in March.