The Central Intelligence Agency considered its spying on American political and civil rights leaders such as Sen. Robert F. Kennedy and the Rev. Martin Luther King Jr. as having the same high priority as its intelligence-gathering on the Soviet Union and Communist China, according to CIA files.

The previously undisclosed files, obtained by The Washington Post last week, were declassified about two years ago by the CIA and turned over to plaintiffs in a civil lawsuit challenging the legality of the CIA'S "Operation Chaos" domestic spying program in the late 1960s and early 1970s.

The documents obtained by The Post are among approximately 200 pages of such material scheduled for public release this week.

The documents, being released by the Center for National Security Studies, a private group exploring alleged intelligence service abuses, include some that might not have been disclosed to two government entitites that probed Chaos after it was made public in late 1975, according to lawyers familiar with those investigations.

Persons who have had access to all the documents turned over to the plaintiffs said that while much of the material is not new in terms of basic information, it places many elements of the program in a new light and details for the first time the extent of opposition within the CIA itself to the domestic spying activity and the priority given the mission.

For example, the CIA'S inspector general reported in a memorandum that Chaos cable traffic to one CIA post "was destroyed immediately after reading so as to avoid any possibility of its somehow falling into the hands of a black officer" who might object to the program.

Various CIA officials questioned the legality of the program at the time, and voiced their concerns at the highest levels of the agency.

However, according to another memo, CIA Director Richard Helms decreed that it should not be stopped "simply because some members of the organization do not like this activity."

Operation Chaos was begun in 1967 when President Johnson asked the CIA to determine whether antiwar activity was being financially or otherwise backed by foreign countries. It was disclosed publicly in The New York Times in late 1975, and was probed at length by a presidential commission headed by Vice President Nelson Rockefeller and a Senate select committee headed by Frank Church (D-Idaho).

The program apparently intensified in May 1969, when Helms instructed that "operational priority of MHCHAOS (the CIA code name) activities in the field is in the highest category, ranking with Soviet and Chicom (Chinese Communist) data," according to a CIA memo.

The CIA has contended that the Chaos program was always a minor part of its activities, with later CIA Director William Colby once describing it to President Ford as a "low-cost collection program."

Within a year after the Helms high-priority instructions, a CIA field office head informed superiors that "I do not think it is the sort of thing that we should be involved in," according to a CIA memo.

He said that even if it were considered "passive" intelligence collecting "there is a natural tendency when an interesting report is received to request additional details, then the action begins." He said the domestic collection of data on U.S. citizens is "clearly the function" of the FBI and not the CIA, and "I think we would find it difficult to justify what we're doing."

The CIA inspector general's report two years later re-emphasized what it call "numerous signs of uneasiness over the agency's role" because CHAOS "appeared to constitute a monitoring of the political views and activities of Americans not known to be or suspected of being involved in espionage."

"Some rather strong language was used in describing what was understood to be the thrust of MHCHAOS and several officers said they wanted no part of it," the inspector general said. He said many officers felt that the agency would "find itself confronting a major crisis" if the program became known publicly.

Helms' reaction, according to another CIA memo, was to suggest that the person heading the program "become identified with the subject of terrorism" rather than domestic spying activities, while continuing the same operation.

There have been previous reports that the CIA kept files on 10,000 Americans and some data on 300,000 others. The recently disclosed materials appear to confirm for the first time the names of some of those watched.

Among those listed in a computer printout were former House member Bella Abzug (D-N.Y.) and Rep. Ronald Dellums (D-Calif.), as well as Kennedy and King.

In addition to the names located on the computer, the CIA also maintained what it called "sensitive files" on Abzug concerning her anti-Vietnam War activities in Europe, on King and on King's widow, Coretta.

An attempt by the plaintiffs to make these documents public in January 1977 was blocked by a federal judge when she was informed that they planned a press conference concerning the material.

The plaintiffs, represented by the American Civil Liberties Union, had U.S. District Court Judge June L. Green reversed by the U.S. Court of Appeals, which said her order preventing disclosure of the materials presented serious First Amendment problems.

Even after the appellate court's ruling, Green questioned the ethics of the ACLU lawyer handling the case and chastised him for wanting the material made public. However, she rejected a Justice Department request that the government be given 72 hours' notice before the material was released.

The government had claimed that the release of the documents then would prejudice the CIA in a full trial before Green later. However, when the court of appeals said the CIA had to prove that any potential harm to the agency would be "substantial and serious," Justice Department attorneys conceded that "we could not even begin to meet this test."

Normal procedure in early phases of a civil lawsuit is for a side turning over documents to the other to ask a judge to sign a "protective order" preventing them from being made public if it feels it is necessary. "Protective orders" require strong justification, and the CIA did not ask for one when it first turned over the material.

After the ACLU informed the CIA of a pending press release, in January 1977, Green cited sections of local court rules concerning out-of-court comments by attorneys and ordered the material kept secret.

The U.S. Court of Appeals said her order was wrong because it prohibited parties in a case from making "political expressions" and was "unsupported by any evidence."

In a hearing in May of this year, Green made it clear that she was still opposed to release of the material and accused ACLU attorney Mark Lynch of "playing games with me." However, she added, "there is nothing that this court can do at this time."