by Scott Shane

WASHINGTON - The Central Intelligence Agency withheld information about a secret counterterrorism program from Congress for eight years on direct orders from former Vice President Dick Cheney, the agency's director, Leon E. Panetta, has told the Senate and House intelligence committees, two people with direct knowledge of the matter said Saturday.

The report that Mr. Cheney was behind the decision to conceal the still-unidentified program from Congress deepened the mystery surrounding it, suggesting that the Bush administration had put a high priority on the program and its secrecy.

Mr. Panetta, who ended the program when he first learned of its existence from subordinates on June 23, briefed the two intelligence committees about it in separate closed sessions the next day.

Efforts to reach Mr. Cheney through relatives and associates were unsuccessful.

The question of how completely the C.I.A. informed Congress about sensitive programs has been hotly disputed by Democrats and Republicans since May, when Speaker Nancy Pelosi accused the agency of failing to reveal in 2002 that it was waterboarding a terrorism suspect, a claim Mr. Panetta rejected.

The law requires the president to make sure the intelligence committees "are kept fully and currently informed of the intelligence activities of the United States, including any significant anticipated intelligence activity." But the language of the statute, the amended National Security Act of 1947, leaves some leeway for judgment, saying such briefings should be done "to the extent consistent with due regard for the protection from unauthorized disclosure of classified information relating to sensitive intelligence sources and methods or other exceptionally sensitive matters."

In addition, for covert action programs, a particularly secret category in which the role of the United States is hidden, the law says that briefings can be limited to the so-called Gang of Eight, consisting of the Republican and Democratic leaders of both houses of Congress and of their intelligence committees.

The disclosure about Mr. Cheney's role in the unidentified C.I.A. program comes a day after an inspector general's report underscored the central role of the former vice president's office in restricting to a small circle of officials knowledge of the National Security Agency's program of eavesdropping without warrants, a degree of secrecy that the report concluded had hurt the effectiveness of the counterterrorism surveillance effort.

An intelligence agency spokesman, Paul Gimigliano, declined on Saturday to comment on the report of Mr. Cheney's role.

"It's not agency practice to discuss what may or may not have been said in a classified briefing," Mr. Gimigliano said. "When a C.I.A. unit brought this matter to Director Panetta's attention, it was with the recommendation that it be shared appropriately with Congress. That was also his view, and he took swift, decisive action to put it into effect."

Members of Congress have differed on the significance of the program, whose details remained secret and which even some Democrats have said was properly classified. Most of those interviewed, however, have said that it was an important activity that should have been disclosed to the intelligence committees.

Intelligence and Congressional officials have said the unidentified program did not involve the C.I.A. interrogation program and did not involve domestic intelligence activities. They have said the program was started by the counterterrorism center at the C.I.A. shortly after the attacks of Sept. 11, 2001, but never became fully operational, involving planning and some training that took place off and on from 2001 until this year.

In the tense months after 9/11, when Bush administration officials believed new Qaeda attacks could occur at any moment, intelligence officials brainstormed about radical countermeasures. It was in that atmosphere that the unidentified program was devised and deliberately concealed from Congress, officials said.

Representative Peter Hoekstra of Michigan, the top Republican on the House intelligence committee, said last week that he believed Congress would have approved of the program only in the angry and panicky days after 9/11, on 9/12, he said, but not later, after fears and tempers had begun to cool.

One intelligence official, who would speak about the classified program only on condition of anonymity, said there was no resistance inside the C.I.A. to Mr. Panetta's decision to end the program last month.

"Because this program never went fully operational and hadn't been briefed as Panetta thought it should have been, his decision to kill it was neither difficult nor controversial," the official said. "That's worth remembering amid all the drama."

Bill Harlow, a spokesman for George J. Tenet, who was the C.I.A. director when the unidentified program began, declined to comment on Saturday, noting that the program remained classified.

In the eight years of his vice presidency, Mr. Cheney was the Bush administration's most vehement defender of the secrecy of government activities, particularly in the intelligence arena. He went to the Supreme Court to keep secret the advisers to his task force on energy, and won.

A report released on Friday by the inspectors general of five agencies about the National Security Agency's domestic surveillance program makes clear that Mr. Cheney's legal adviser, David S. Addington, had to approve personally every government official who was told about the program. The report said "the exceptionally compartmented nature of the program" frustrated F.B.I. agents who were assigned to follow up on tips it had turned up.

High-level N.S.A. officials who were responsible for ensuring that the surveillance program was legal, including the agency's inspector general and general counsel, were not permitted by Mr. Cheney's office to read the Justice Department opinion that found the eavesdropping legal, several officials said.

Mr. Addington could not be reached for comment on Saturday.

Questions over the adequacy and the truthfulness of the C.I.A.'s briefings for Congress date to the creation of the intelligence oversight committees in the 1970s after disclosures of agency assassination and mind-control programs and other abuses. But complaints increased in the Bush years, when the C.I.A. and other intelligence agencies took the major role in pursuing Al Qaeda.

The use of harsh interrogation methods, including waterboarding, for instance, was first described to a handful of lawmakers for the first time in September 2002. Ms. Pelosi and the C.I.A. have disagreed about what she was told, but in any case, the briefing occurred only after a terrorism suspect, Abu Zubaydah, had been waterboarded 83 times.

Democrats in Congress, who contend that the Bush administration improperly limited Congressional briefings on intelligence, are seeking to change the National Security Act to permit the full intelligence committees to be briefed on more matters. President Obama, however, has threatened to veto the intelligence authorization bill if the changes go too far, and the proposal is now being negotiated by the White House and the intelligence committees.

Representative Jan Schakowsky, a Democrat of Illinois on the House committee, wrote on Friday to the chairman, Representative Silvestre Reyes, a Democrat of Texas, to demand an investigation of the unidentified program and why Congress was not told of it. Aides said Mr. Reyes was reviewing the matter.

"There's been a history of difficulty in getting the C.I.A. to tell us what they should," said Representative Adam Smith, a Democrat of Washington. "We will absolutely be held accountable for anything the agency does."

Mr. Hoekstra, the intelligence committee's ranking Republican, said he would not judge the agency harshly in the case of the unidentified program, because it was not fully operational. But he said that in general, the agency had not been as forthcoming as the law required.

"We have to pull the information out of them to get what we need," Mr. Hoekstra said.