Iranian President Mahmoud Ahmadinejad speaks to a nearly empty room at the United Nations headquarters after several nations, including Canada, walked out in protest of the speech on Wednesday. (Jason DeCrow/Associated Press)

Canada boycotted a speech by Iranian President Mahmoud Ahmadinejad to the UN General Assembly on Wednesday evening, protesting his denial of the Holocaust and verbal attacks on Israel.

The Canadian delegation, led by Foreign Affairs Minister Lawrence Cannon, walked out at the start of Ahmadinejad's address. Several other delegations, including lower-level U.S. diplomats, left during the speech. Israel's UN delegation was not present for the speech.

Ahmadinejad speaks out against Israel, the West and capitalism in his address to the UN General Assembly on Wednesday. (Jason DeCrow/Associated Press)

Ahmadinejad's address to a half-empty chamber in New York slammed Israel and railed against the West and capitalism.

He criticized Israel for staging "barbaric" attacks in the Gaza Strip last year, and he slammed the U.S.-led wars in Iraq and Afghanistan.

Ahmadinejad didn't talk about his country's contentious nuclear program, instead calling for the end of all nuclear, chemical and biological weapons.

Earlier Wednesday, Prime Minister Stephen Harper said Ahmadinejad's "absolutely repugnant remarks" previously made about the Holocaust were reason enough for Canadian officials to boycott the Iranian president's address.

"There are times when things are being said in this world that it is important that countries that have a moral compass stand up, make their views known," Harper said in Oakville, Ont.

"And our absence there will speak volumes about how Canada feels about the declarations of President Ahmadinejad."

Holocaust denial

Ahmadinejad has repeatedly made comments denying that six million Jews were killed during the Second World War. Earlier this month, Ahmadinejad claimed again that the Holocaust was a lie and a pretext for occupying Palestinian lands.

Prime Minister Stephen Harper says Ahmadinejad's "absolutely repugnant remarks" about the Holocaust are reason enough for Canadian officials to boycott the Iranian president's address. (CBC)

"President Ahmadinejad has said things, particularly about the state of Israel, the Jewish people and the Holocaust, that are absolutely repugnant," Harper said.

"It is unfitting that somebody like that would be giving those kinds of remarks before the United Nations General Assembly. Canada does not want to be equivocal at all in terms of our view on that. We find it disgraceful, unacceptable, and we’re going to be absolutely clear on that."

Harper said the government is also bothered by Iran's crackdown on legitimate dissent, "the fiasco" surrounding this summer's elections and the continued detention of a Canadian journalist without charges.

Maziar Bahari, an Iranian-Canadian reporter, was imprisoned while covering the election unrest for Newsweek.

Harper, who was in Oakville to announce the return of Tim Hortons to the Canadian corporate family, defended his decision not to attend the UN General Assembly.

He said it's standard for Canada's foreign affairs minister to be the representative.

"My speaking slot this year was scheduled the same time as the G-20 in Pittsburgh, and we chose the G-20, which is what all other world leaders are doing," Harper said.

With files from The Canadian Press