It was not clear whether the espionage investigation was directly related to the secret meetings with Mr. Ghorbanifar

It was not clear whether the espionage investigation was directly related to the secret meetings with Mr. Ghorbanifar. Nor was there immediate evidence of whether money had changed hands in exchange for classified information.

American policy towards Iran is now of critical importance to Israel, which is increasingly concerned by evidence that Tehran has accelerated its program to develop a nuclear weapon. The NIKE SHOX Administration has become concerned that Israel might move militarily against Iran’s nuclear complex in order to delay Tehran’s progress.

American counterintelligence officials say that Israeli espionage cases are difficult to investigate, because they involve an important ally that enjoys broad political influence in Washington. Several officials said that a number of espionage investigations involving Israel had been dropped or suppressed in the past in the face of political pressure. The last major Israeli spy case to become public involved Jonathan Pollard, a Naval intelligence analyst who was arrested in 1985 for passing large volumes of classified material to his Israeli intelligence handlers. He was sentenced to life in prison, and over the years, Israeli officials have lobbied a succession of American presidents to try to win his release.