Israel’s ambassador to the United Nations called on world leaders Thursday to boycott Iranian President Mahmoud Ahmadinejad’s September 26 speech to the 67th General Assembly of the world body in New York.

“Any country that sits in during Ahmadinejad’s speech is in violation of the United Nations Charter,” which forbids member states from threatening other member states, Ambassador Ron Prosor told the Times of Israel on Thursday.

The Iranian regime “constantly invents new terms in the English language for liquidation, eradication and erasing of Israel and Jews from the pages of history. One cannot be quiet in the face of these anti-Semitic rants, yet we don’t hear any outcry from the international community,” he charged.

That language, coupled with the regime’s defiance of Western and UN Security Council demands to allow oversight of its alleged efforts to obtain the capability to build nuclear weapons, have convinced many Israeli leaders that Iran is actively seeking to follow through on those threats.

At the Non-Aligned Movement summit in Teheran in late August, UN Secretary-General Ban Ki-moon responded to Western criticism of his decision to attend the high-level meeting in the Iranian capital by openly castigating Iran’s leaders for their Holocaust denial and calls to destroy the Jewish state.

“I strongly reject threats by any member state to destroy another or outrageous attempts to deny historical facts such as the Holocaust,” Ban said.

“Claiming that Israel does not have the right to exist or describing it in racist terms is not only wrong, but undermines the very principle we all have pledged to uphold,” he added.

But Israel’s Prime Minister Binyamin Netanyahu was not satisfied with the UN chief’s remarks, which Israeli officials noted did not even specify Iran by name.

“In Tehran today, the representatives of 120 countries heard a blood libel against the State of Israel and were silent,” Netanyahu charged in an August 30 statement after Iranian leaders once again called Israel a “cancer” at the summit.

“This silence must stop,” Netanyahu said. “Therefore, I will go to the UN General Assembly and, in a clear voice, tell the nations of the world the truth about Iran’s terrorist regime, which constitutes the greatest threat to world peace.”

The general debate portion of the General Assembly begins September 25. Iran’s President Mahmoud Ahmadinejad is expected to speak before the assembled delegates the following day, on September 26. Last year, Ahmadinejad used his speech to promote conspiracy theories about the Holocaust and the September 11 attacks, and sparked a mass walkout of roughly one-third of the assembled diplomats and world leaders.

This year, the date of Ahmadinejad’s speech falls on Yom Kippur, the Jewish calendar’s most solemn day of fasting and atonement, which some Israeli officials are calling an especially poignant time for the world’s largest diplomatic summit to sit and listen to a man who threatens Israel with destruction and has questioned the historical veracity of the Holocaust.

Netanyahu will arrive in New York on September 27. Despite conflicting reports, Israeli officials have said he will likely not meet with US President Barack Obama during the visit.

Netanyahu is expected to use his UN speech to call for ever harsher sanctions against Iran’s nuclear program.

According to Prosor, stopping Iran’s nuclear program “is not Israel’s problem. An Iran with nuclear weapons, under the ayatollahs, with delivery systems [for nuclear warheads], is a huge threat to the entire regional strategic environment, to the Saudis and others.”

Prosor called on the international community to assert its will on the issue. “Diplomacy is an important tool in the toolbox. We should work with diplomacy and economic sanctions. But the international community should repeat — and mean — that all options are on the table,” a reference to possible military strikes at Iran’s nuclear installations if diplomacy fails.

Prosor indicated that Israeli officials are growing impatient at the pace of diplomacy.

“Iran’s nuclear program is like an express train from New York to Washington, and the international community’s response is like a local train that stops at every stop,” he warned. “At one stop Russia wants to get off, at another someone else wants to get on. In order to work, diplomacy has to build up the speed” required to stop the nuclear program, he said.

“The international community doesn’t have the option of doing nothing,” he concluded.