It wasn't the first time the Canadian delegation has snubbed Ahmadinejad — they walked out last year and in 2009 at the United Nations annual gathering of world leaders.
But tensions are running higher than ever between the two countries after Foreign Affairs Minister John Baird shuttered Canada's embassy in Iran three weeks ago.
In Ottawa, Baird said Canada's boycott of Ahmadinejad's "bizarre" speech at the United Nations General Assembly — during which American and Israeli officials also walked out — sent a strong message.
"Canada didn't want to be associated in any way, shape or form with the ramblings of an anti-Semitic hate-monger," he said. "Obviously we don't want to give it any credibility by even being there. I noticed the government of Barack Obama made the same conclusion, which I think was wise."
Ahmadinejad was dismissive of Canada in a news conference following his speech to the UN.
"Any country is free to have or to not have relations with other countries," he said.
"I fundamentally don't see this as a very important issue. Of course we did not have a substantial economic relationship with Canada."
Ahmadinejad didn't mention Canada by name during his speech to the United Nations General Assembly, but a statement posted Wednesday by the Islamic Republic News Agency, Iran's official news agency, was making headlines all the same.
The statement, attributed to Iran's Foreign Ministry, warned Iranian citizens against travelling to Canada, citing "Islamophobia," "Iranophobia" and a "double standard" in Canada towards human rights.
Baird was unequivocal in his scorn for the statement.
"I think it's absolutely ridiculous, and I think 99 per cent of Canadians would share that view," he said.
On Sept. 7, Baird abruptly announced that Canada had shut down its embassy in Tehran and ordered personnel at the Iranian embassy in Ottawa to leave the country within five days.
"There have been cases of arrest and expulsion of Iranian expatriates under various pretexts and Iranians are deprived of their basic rights to continue with their ordinary activities, including the right to access their banking accounts and do ordinary transactions," the Iranian Foreign Ministry statement said.
In the past, Ahmadinejad has used the UN spotlight to attack Israel, cast doubt on the Holocaust and question American accounts of the terrorist attacks of Sept. 11, 2001.
There was some of the same in Wednesday's speech, but in his final address to the UN, Ahmadinejad also took on a loftier tone as he described a new world order.
In what sounded like a sermon at times, Ahmadinejad envisioned a world that lacks the "hegemony of arrogance," citing what he called the "continued threat by the uncivilized Zionists to resort to military action against our great nation."
A saviour will soon emerge who will change the world, he added.
"I do not believe that Muslims, Christians, Jews, Hindus, Buddhists, and others have any problems or are hostile against each other," he said.
He made no reference to Iran's nuclear program. The United States, Israel, Canada and others fear that program is little more than a pretence for building a nuclear weapon for use against the Israelis.
Iran, however, insists its a peaceful program. The country has been subjected to tough sanctions for its refusal to co-operate with the UN's nuclear watchdog agency; the UN has asked for proof that its intentions are peaceful as Iran enriches uranium to levels that would allow the construction of a nuclear bomb.
Baird said Canada is pushing for even tougher sanctions.
"We're always ready to implement new sanctions against Iran ... we're always ready to do even more than what we've done up until now," he said in French on Parliament Hill.
"We're working now with our allies to see to it that the sanctions be even stronger. We're much more active than some of the other countries; that's important."
Israel has been pounding the drum beat of war against Iran for months. Israeli Prime Minister Benjamin Netanyahu has been criticized for attempting to pressure the U.S. into joining Israel in launching a military strike.
U.S. President Barack Obama, who addressed the UN himself earlier this week in a forceful rebuke of the recent anti-American violence in the Middle East, says the dispute can still be resolved through diplomacy. But he's also pledged to prevent Iran from building a bomb.
Ahmadinejad assailed both the United States and Israel in his speech, accusing Americans of protecting a nuclear-armed "fake regime." That shot at Israel prompted the country's UN ambassador to walk out.
The Iranian leader spoke despite the concerted efforts of some, including Liberal MP Irwin Cotler, to convince UN Secretary General Ban Ki-moon to pull the plug on his participation.
"Allowing President Ahmadinejad to address the UN General Assembly is a cruel parody of law and justice that will put us on the wrong side of history," Cotler wrote in a recent letter to the secretary general and U.S. Secretary of State Hillary Clinton.
The letter cited Ahmadinejad for human rights violations, pursuit of nuclear weapons in defiance of the UN and incitement to genocide.
Cotler said the UN should be indicting Ahmadinejad, not inviting him to the podium.
Canada isn't alone in its outrage about Ahmadinejad. Thousands of protesters streamed into a plaza near the United Nations complex in mid-town Manhattan on Wednesday as the Iranian leader addressed the annual gathering.
Former New York City Mayor Rudolph Giuliani and Newt Gingrich, the one-time Republican presidential hopeful, made appearances at the protest. Syrians were also on hand to denounce Iran's support of Syrian President Bashar Assad's bloody crackdown against his opponents.
Prime Minister Stephen Harper has decided once again not to speak to the opening of the assembly's fall session. The UN has met seven times since Harper was elected prime minister; he's addressed the General Assembly only twice.
In his place, Baird will speak at the UN on Monday.
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