Responding to questions about what motivated Ottawa’s unexpected decision to sever diplomatic ties with Tehran, Foreign Affairs Minister John Baird says he isn’t aware of imminent military action against Iran.

“I can confirm that we have no knowledge whatsoever of any outside military action, whether it’s from the United States or from Israel,” Baird said in an interview that was broadcast on CTV’s Question Period on Sunday.

Questions about motive have been swirling since Friday when the government announced the closure of its embassy in Tehran and the expulsion of Iranian diplomats from Ottawa.

Both Baird and Prime Minister Stephen Harper cited the safety of Canada’s diplomats as a factor in the decision, saying concern for ambassadors has been growing since protesters stormed the British embassy in Iran on Nov. 29, 2011.

“We just felt at this time it is no longer safe and secure to have these Canadians working there and that weighed heavily on me,” Baird said in an interview from the Asia-Pacific Economic Cooperation summit in Vladivostok, Russia.

Since the decision was announced Friday-- the same day Canada formally listed Iran as a state sponsor of terrorism -- speculation has focused on whether the decision was a pre-emptive response to a planned Israeli attack on Iran. Baird has denied those rumours.

Among the other reasons provided for the closure is Iran’s burgeoning nuclear program, ongoing rhetoric against Israel and political support for the regime of Bashar Assad in Syria.

A senior official has confirmed to CTV News that there is a credible threat against Canadian diplomats in Tehran, but when asked about this, Baird declined to delve into particulars.

“What I can say is that this country, Iran, has not respected the Vienna convention on the treatment of diplomats,” he said, later adding that he would not be discussing “specific security assessments.”

Iran responds

The Iranian Foreign Ministry has referred to Canada’s decision to halt their relationship as hostile, unwise and unconventional. This sentiment was also reflected in a note on the door of the Iranian embassy in Ottawa, where Iranian diplomats only have only two days left to leave.

Iran has already started to respond to the swift embassy closure, with the country’s parliamentary speaker cancelling a planned visit to Canada next October to protest the decision.

At the APEC conference in Russia, Prime Minister Harper said Sunday that nothing Iran does in response to the Canadian embassy closure would surprise him, given that the diplomats were recalled due to Iran’s "capacity for increasingly bad behaviour.”

While Iranian officials disapprove, Israeli Prime Minister Benjamin Netanyahu has welcomed Canada’s decision. Netanyahu reportedly suggested that the move might dissuade Iran from moving forward with its nuclear program, which he has alleged is a weapons program.

In the meantime, critics who are wary of Ottawa’s decision says it’s difficult to judge the move without knowing more about the safety concerns the government said it acted on.

Still, NDP Foreign Affairs critic Paul Dewar has taken issue with the unexpected announcement.

“For us to make a difference, we have to be there. We have to show up, and now we’re walking away,” Dewar told CTV News earlier this weekend.

Interim Liberal Leader Bob Rae also frowned on the move, arguing that differences of opinion cannot be the only reason to sever lines of political communication.

“The simple fact is we don’t cut off diplomatic relations with every country we disagree with,” he told CTV News.

Ottawa made the decision under the Justice for Victims of Terrorism Act, which was enacted in March 2012 and requires the federal government to assemble a list of countries which it considers state sponsors of terrorism.

Speaking with CTV’s Question Period, Baird called it “undeniable” that Iran was supporting the Lebanon-based Hezbollah and Hamas, a similar group in the Gaza Strip.

“I think we have to speak the truth, we have to be honest, we have to be upfront and we’re doing that,” Baird said.

With a report from CTV National News’ Roger Smith