White House press secretary Jody Powell today accused Sen. Jake Garn (R-Utah) of leaking "inaccurate" and "distorted" information about the United States' ability to verfiy Soviet compliance with a new strategic arms limitation treaty (SALT).

Powell, who later backed off from his assertion that Garn was the source, was commenting on a report published Tuesday in The New York Times suggesting that U.S. ability to verfiy the terms of a SALT accord was severely damaged by the loss of intelligence stations in Iran.

The report said Central Intelligence Agency Director Stansfield Turner had told senators that it would take five years to make up fully for the loss of intelligence-gathering capability in Iran.

Defense Secretary Harold Brown denied the report Tuesday, saying the United States expects to conclude a SALT II accord "that resolves satisfactorily the remaining provisions on verification."

Powell discussed the report with reporters here as President Carter entered the seventh day of a vacation on nearby Spaelo Island.

Powell noted that Brown said the United States can compensate within one year for the loss of intelligence-gathered facilities in Iran that would have been relied on to verify Soviet compliance with a SALT agreement. He said this was too short a time for the Soviets to obtain secretly any king of strategic advance over he United States outside the terms of the treaty.

In an elaboration of his earlier statement, Brown yesterday told CBS News that he is convinced the United States is "going to be able to verify a SAFT agreement from the moment it is signed and ratified."

He predicted his statement on "the variety of our monitoring techniques and . . the extended time that it takes for the Soviets to test a missile-it takes them 20 tests and some years . . ."

Powell said that Turner's estimate of five years concerns the time it will take to make up for the loss of all intelligence assets in Iran, not all of which would have been used to verify SALT II.

"It is apparent that The Times was given an inaccurate account of Adm. Turner's testimony," Powell said.

Garn later issued a statement declaring that neither he nor his staff was the source of any leaks concerning the loss of U.S. intelligence-gathering capability in Iran.

"Nothing could be further from the truth," Garn said. ". . . I think it is ironic that I would be accused of leaking information when I was among the first to criticize the Carter administration for selectively leaking information that would indicate that the SALT II treaty would be verifiable."

Powell told reporters this morning that he "understood" that Garn was the source of the information, adding that if Garn "worked for the administration, he no longer would." But later, Powell backed off from this assertion, saying he did not mean to imply he knew the source of The Times report.

Garn is a conservative Republican and staunch opponent of a new SALT agreement. The treaty, now in the final stages of negotiation, has become the subject of intense maneuvering centering on various estimates and reports-such as that in The Times-on whether compliance can be verified.

Ever since the Iranian revolution, administration officials have insisted that U.S. ability to verify a SALT accord was not seriously compromised by the loss of the intelligence-gathering facilities in Iran and that the administration was moving vigorously to make up for what losses occurred. The president has pledged repeatedly that he will not sign a treaty that cannot be adequately monitored and verified for compliance by the Soviets.

Powell said today that the "inaccurate report" in The Times can be "easily corrected," but that it is important that the Senate be given accurate information and that the administration is at a disadvantage in trying to provide it because of leaks to reporters.

He said the administration cannot discuss publicly the steps it is taking to verify the treaty without risking Soviet countermoves or disclosing U.S. intelligence-gathering sources and methods, thereby rendering them ineffective.

Powell made the comments about Garn less than an hour after arriving here after several days of vacation.

He also told reporters that Carter jogged four or five miles on Sapelo Island this morning and later went fishing with two friends.

Rosalynn Carter left Sapelo Island this morning and flew to Raleigh, N.C., where she spoke at the opening of the Governors' Conference on Metal Health. She returned late today.