Canada has closed its embassy in Iran and will expel all remaining Iranian diplomats in Canada within five days.
Foreign Minister John Baird said in a statement on Friday that the Iranian government was "the most significant threat to global peace and security in the world today".
He cited the country's nuclear programme and its "increasing military assistance to the Assad regime" in the list of Canadian grievances with Iran.
Iran's semi-official Mehr news agency reported that Canada's decision was "in co-operation with America's hostile policies against Iran".
The first shot across the bow in this recent row might have come when Hamid Mohammadi, Iran's cultural affairs counsellor, encouraged Iranian-Canadians to seek "high-level" positions and to maintain their Iranian identities.
In response, Canada's Foreign Affairs department told a Canadian newspaper in July that, "The Iranian Embassy should not interfere in their choices. Canadian security organisations will act to prevent threats and intimidation of Canadians.”
Al Jazeera called Baird's office to ask about the timing of this emabssy's closure and the weight of Mohammadi's comments. We did not receive a response.
Ramin Mehmanparast, spokesperson for Iran’s foreign ministry, told Iran's ISNA news agency that “the current Canadian government is extremist and severely under the influence of the Zionist regime”.
He also said the successes of the recent NAM summit proved the West's diplomatic failures and showed that Iranian people have continued to thrive despite the sanctions levelled against the country.
Elizabeth Berton-Hunter, spokesperson for Amnesty International in Toronto said that the move to cut diplomatic ties on this level will make appealing to the Canadian government to take action on cases in Iran "difficult to do now".
"It is a great concern - there's no doubt about it," said Berton-Hunter, who pointed to the the right's group's recent report on the quickening pace of Iran's executions as a reason why families of those facing punishment in Iran would be worried.
Unknown is the impact of severed diplomatic ties on the cases of Iranian-Canadians in trouble in Iran, such as blogger Hossein Derakhshan (currently serving a 19-and-a-half year prison sentence on spying charges), Hamid Ghassemi-Shall (who has been sentenced to death on charges of espionage and is awaiting execution) and Saeed Malekpour, a software developer accused of spreading indecent material online, who is also on death row.
Ghassemi-Shall's wife, Antonella Mega, said she was "disappointed" to hear of the decision on behalf of the Canadian government.
"When I received the news this morning I was trying to digest what that meant, and all I can think of is that this means that a potential dialogue has been closed," said Mega, who has not seen her husband since he left for Iran in May of 2008.
"This closing of the relationship between Canada and Iran leaves me doubtful. I just don't know how they're going to help Hamid; of what their plans are."
Mega said that when she has the opportunity to speak to her husband on the phone, she tries to reassure him that Iranian authorities will free him.
"The Iranian government is in charge of Hamid's case, so I do depend on their kindness ... but obviously I count on the Canadian government to advocate for him," Mega said.
While many Iranians decried the decision on social media sites, some support it, and, in fact, have been calling for such a move by the Canadian government.
Rights activist Shabnam Assadollahi, who had co-translated the entire text of Mohammadi's interview and posted it on Facebook along with a plea to the Canadian government to shut down the embassy, said that "for 33 years they have had an embassy here and for 33 years we've been trying to have an open dialogue with the Islamic Republic of Iran - it has gone nowhere".
"In these 33 years, what have we been able to do for our poor people there? Even during the recent earthquake, what could we do?" Assadollahi told Al Jazeera from Ottawa.
"The UK and the US have already shut their embassy. Israel has not had an embassy there since the Islamic Revolution," said Assadollahi, who feels Iran's influence in Canada - especially its education system - is a threat to Canada's national security.
"If three of Canada's allies don't have embassies in Iran, why should Canada?"
A Conservative stance
Al Jazeera's Daniel Lak, reporting from Toronto said that the two countries have not had "anything resembling cordial relations" since the 1979 Islamic Revolution.
He said that most recently, the chilled relations between the two countries "has to do with [Prime Minister] Stephen Harper's Conservative government just taking a very firm, explicit line on Iran," Lak said.
In January, Harper described Iran as "fanatically religious" and "dangerous" to Canadian broadcaster CBC.
"In my judgement, these are people who have a particular, you know, a fanatically religious world view, and their statements imply to me no hesitation about using nuclear weapons if they see them achieving their religious or political purposes. And … I think that’s what makes this regime in Iran particularly dangerous." he said.
Canada's relations with Iran have been particularly rocky since Iranian-Candian photojournalist Zahra Kazemi died while being detained in Evin prison in 2003, and again, in 2009, when Maziar Bahari, also a dual citizen and a journalist, was detained for over 100 days.
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