JERUSALEM — An international missile-defense symposium scheduled for the Knesset Tuesday was canceled after the organizer was accused of having likened former prime ministers Shimon Peres to a Nazi collaborator and Yitzhak Rabin to a dictator.

Organizer Robert Loewenberg, president of the Institute for Advanced Strategic and Political Studies, Jerusalem and Washington, had scheduled an afternoon conference to be addressed by U.S. House Speaker Newt Gingrich, and by satellite by Turkish Prime Minister Mesiut Yilmaz.

But the day before the conference was to begin, reports began circulating that in a 1997 report on the Middle East peace process, Loewenberg had compared Peres to a Nazi. Several Labor Party MKs then said they would prevent the conference from being held.

By 10 a.m., three hours before the symposium was to start, Gingrich had canceled his appearance, the Knesset had refused to allow the parley to be held, and the Defense Ministry had withdrawn its sponsorship.

Gingrich and Knesset Speaker Dan Tichon decided after joint consultations against going ahead with the symposium. Meretz leader Yossi Sarid and Labor MKs had said they would ensure that Loewenberg could not speak or lead the discussion. Deputy Defense Minister Silvan Shalom and Labor MK Binyamin Ben-Eliezer, who were meant to appear on the panel, both canceled their participation.

Loewenberg called the accusations ridiculous, saying his report had spoken of Peres as somebody who denies reality.

In a 49-page essay written in 1997, Loewenberg wrote that Rabin "effectively transformed Israel into a police state" in trying to crush opposition to his land-for-peace agreement with the Palestinians.

In the paper, Loewenberg also argued that the Jews killed by Palestinian terrorism after the 1993 Oslo accords were victims of peace. In the argument, he compared Peres to Rudolph Kastner, the Hungarian Jew who during World War II negotiated with Adolf Eichmann to save some 1,600 Hungarian Jews.

"The charges themselves are gross," Loewenberg said. "My paper speaks for itself." He said the charges were raised "for the obvious purpose of preventing this discussion and embarrassing our allies," referring to Gingrich and the U.S.

Two of the institute's missile experts, Angelo Codevilla and William Van Cleave, both regarded as leading strategists in the U.S., said their message to the conference and Gingrich was that Israel's Arrow anti-missile defense system would not be able to protect the country against the medium-range ballistic missiles being developed by Iran with Russian aid.

They called for the U.S. and Israel to jointly develop a space-based missile defense system that would enable satellites to track enemy missiles from launch and fire an interceptor that could destroy incoming rockets far away from population centers threatened by their chemical or biological warheads.

Currently, the Clinton administration opposes such a program, Codevilla and Van Cleave said, because it regards this as a violation of the 1972 U.S.-Soviet ABM Treaty.

Loewenberg said he would reschedule the conference, probably in Washington, and that Gingrich did not rule out attending a forthcoming parley.

Sarid expressed "satisfaction at the decision to cancel the symposium without the need for torpedoing it. In the future it will be clear to all those who prepared the ground for the murder of Rabin that they are persona non grata in Israel and the gates of the Knesset are closed to them."