Washington — A member of President Obama’s advisory committee on signals intelligence, the panel that recommended major restrictions on the National Security Agency’s data collection, on Sunday countered the notion that the panel had found no value in the agency’s activities.

Michael J. Morell, a former acting director of the Central Intelligence Agency, said that although the panel of independent experts did not find evidence that the National Security Agency’s efforts had helped stop a terrorist attack, the ability to monitor whether foreign terrorists were calling Americans remained important. The panel released its report on Wednesday.

Among its 46 recommendations to Mr. Obama, the panel suggested that a third party, like the telephone companies or a private consortium, hold on to the logs of phone numbers and call durations gathered by the agency. Officials would then have to obtain a court order each time they wanted to access such information.

Such a change would be the first significant restriction on the agency’s surveillance powers since 9/11. Mr. Morell said on the CBS program “Face the Nation” that it would add just a few days to the process of obtaining that data, with emergency exceptions.