By Reuters

(Reuters) - Iran's president said on Wednesday his country was under constant threat of military action from "uncivilized Zionists" and called for a new world order not dominated by Western powers in the service of "the devil."

In his eighth and likely final address to the U.N. General Assembly's annual gathering of world leaders, Mahmoud Ahmadinejad painted a gloomy picture of a world driven by greed rather than morality.

"The current abysmal situation of the world and the bitter incidents of history are due mainly to the wrong management of the world and the self-proclaimed centers of power who have entrusted themselves to the devil," Ahmadinejad said.

Iran's president did not reiterate his comments to journalists in New York on Monday that Israel has no roots in the Middle East and would be "eliminated."

However, he complained that nations were being forced to accept a new era of hegemony and added, in a clear reference to Israel: "Continued threat by the uncivilized Zionists to resort to military action against our great nation is a clear example of this bitter reality."

On Tuesday, in his address to the General Assembly, U.S. President Barack Obama said he would do whatever it takes to prevent Iran from getting nuclear arms, adding that there is not an unlimited amount of time to solve the matter via diplomacy.

Israel and the United States have both refused to rule out the possibility of an armed strike on Iran's nuclear facilities, which the West suspects aim to produce atomic bombs but which Tehran says are for solely peaceful purposes.

Israeli Prime Minister Benjamin Netanyahu, who is due to speak at the United Nations on Thursday, has criticized Obama's position that sanctions and diplomacy should be given more time to stop Iran from acquiring nuclear weapons.

He has called for Obama to spell out "red lines" that, if crossed by Iran, would trigger an attack, something the White House has so far rejected.

U.N. diplomats and nuclear experts say Iran appears to be making headway in building a research reactor that could yield potential nuclear weapons material, adding to growing Western concerns about Tehran's atomic aims.

On Wednesday, Netanyahu promised a tough response at the United Nations to Ahmadinejad's verbal attacks, which coincided with Yom Kippur, one of the most important holidays in the Jewish calendar.

"We are all united in the goal of preventing Iran from achieving nuclear weaponry," he said in open letter to Israelis before boarding a flight to New York.

"On Yom Kippur eve, sacred to the Jewish people, the Iranian tyrant chose to call publicly before all of the world for us to vanish. This is a black day for those who chose to remain in the auditorium and hear these hateful words," Netanyahu added.

Representatives of the United States, Canada and Israel chose not to be present in the U.N. auditorium for Ahmadinejad's speech on Wednesday.

SYRIA CRISIS

Iran has been criticized at the 193-nation General Assembly for allegedly supplying arms to help Syrian President Bashar al-Assad crush rebels in an 18-month conflict that began with peaceful anti-government protests and evolved into a civil war.

Ahmadinejad has denied providing Syria with arms.

In the latest violence, a rebel bomb attack reduced the army headquarters in Damascus to a smoldering wreck, the biggest attack in the Syrian capital since July 18 when a bomb killed Assad's brother-in-law, the defense minister and a general.

While dozens of leaders have decried Syria's civil war at the General Assembly, none have offered concrete proposals on ending it.

Illustrating disagreements within the Arab world, Egyptian President Mohamed Mursi said his nation opposed foreign military intervention in Syria a day after Qatar's leader urged Arab nations to intervene directly to stop the bloodshed in Syria.

At a news conference later on Wednesday, Ahmadinejad said Iran is "capable of avoiding and neutralizing" efforts to sabotage its nuclear facilities, while repeating that his country is open to talks with the United States.

"We are ready for a dialogue and a resolution of problems. ... We have never had any problems with the people of the United States," he said.

In his U.N. address, without mentioning the United States by name, the Iranian president took aim at Washington's global dominance, asking: "Are we to believe that those who spend hundreds of millions of dollars on election campaigns have the interest of the people of the world at their hearts?"

Ahmadinejad, whose own second and final term in office ends next year, said authority should be used as a sacred gift, "not a chance to amass power and wealth."

Iran is under sanctions imposed by the United Nations and Western powers for its refusal to comply with U.N. Security Council demands to halt its nuclear enrichment program.

Ahmadinejad said the 15-nation council, on which the United States, Britain, France, Russia and China all have vetoes, was dominated by "a limited number of governments," preventing the United Nations from acting in a just and equitable way.

Declaring that he represented "a great and proud nation that was a founder of human civilization," Ahmadinejad said: "There is no doubt that the world is in need of a new order and a fresh way of thinking."

His speech touched on issues he has raised in previous U.N. appearances, such as suggesting there should be an "independent fact-finding team" established to discover the "truth" behind the September 11, 2001 attacks on the United States and complaining about the "hegemonic policies and actions of world Zionism."

About a hundred opponents of the Iranian government protested across the street from the United Nations as Ahmadinejad spoke, bearing signs reading "Secular Democracy for Iran."