"My charge is spying for the Israeli government ... I accept this accusation. In connection with my political ... economic and social activities, I spied for Israel," Hamid "Danny" Tefilin said in the taped interview.
Israel dismissed his statement as "ludicrous." The confession has heightened a power struggle between the hard-line clergy and reformers who want nothing to come in the way of improving ties with the outside world.
"I received some training in carrying out my missions and activities during my trip to Israel (six years ago)," Tefilin said.
"I gathered information with the help of a network. Of course, we also gathered information from Muslims through some schemes," Tefilin, wearing a prison uniform, told the interviewer.
The television did not say whether the interview was taped in connection with the closed-door trial of Tefilin in the southern city of Shiraz Monday.
Iran's state media often broadcast taped "confessions" of defendants in political and security cases.
Tefilin and 12 other Iranian Jews are accused of spying for Israel, Iran's arch-foe. Iranian officials say eight Muslims have also been held in the case.
Elahe Sharifpour-Hicks, a New York-based representative of Human Rights Watch, Monday asked the judge to allow an international observer or a member of the Jewish community to attend the trial. She says that request was refused on the grounds of "national security."
Defense lawyer Esmail Nasseri has denied that his clients are guilty and says that any acts they may have committed did not meet the legal standard for espionage and did not involve classified material.
He said confession alone was not sufficient for conviction.
Iranians convicted of spying usually receive long prison terms, but they can be executed if they are found to have "endangered national security." Two Jews were executed at Tehran's Evin prison three years ago.
Hossein Ali Amiri, regional head of the judiciary conducting the trial, says Dani Tefilin has confessed to delivering "sensitive information" to the Mossad, Israel's main external intelligence agency. Referring to Tefilin, Amari adds: "His case is finished."
Tefilin has asked the court for clemency. He was the first of the suspects to be arrested more than a year ago and his brother is among the suspects charged.
Iran maintains that religion has no bearing on the case and notes that eight Muslims have also been arrested.
Iranian Jews numbered 80,000 before the 1979 Islamic revolution; 25,000 remain today. Jews in Iran are generally allowed to practice their religion freely, but they cannot travel to Israel, or have any contact with Israel.
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