Updated

Iran's parliamentary speaker canceled on Saturday a visit to Canada to protest Ottawa's decision to cut diplomatic relations, and Tehran's foreign ministry called "unwise" a five-day deadline set by Canada for Iranian diplomats to leave the country.

Canada shut its embassy in Tehran on Friday accusing the Islamic Republic of being the most significant threat to world peace. The surprise action reinforces the Conservative government's close ties with Tehran's arch foe Israel.

To protest the cutting of ties, Iran's parliamentary speaker Ali Larijani decided not to attend a meeting of legislators from different countries scheduled for late October, Fars news agency said.

Tehran's Foreign Ministry meanwhile said that Ottawa's five-day deadline for its diplomats to leave was "unwise." It said Canada cut relations in an "unprofessional, unconventional, and unjustifiable manner while resorting to misusing international law."

The U.S. and its allies are at loggerheads with Iran over its nuclear program, which the West says is aimed at developing weapons technology. Iran denies the charge, saying its nuclear activities are aimed at peaceful purposes like power generation and cancer treatment.

Washington has not had diplomatic ties with Iran since the aftermath of that country's 1979 Islamic revolution. Canada's break with Iran removes another channel for the United States to get first-hand diplomatic assessments of Iranian affairs. Canada and Britain had been main conduits of information for the U.S., but Britain downgraded its diplomatic relations with Iran after a crowd attacked its embassy in Tehran in November.

Canadian Foreign Affairs Minister John Baird gave a long list of reasons for Ottawa's decision, including Tehran's support for Syria's embattled President Bashar Assad in that country's civil war.

Iran's Foreign Ministry statement countered that Canada violated the human rights of Canadian Indians.

Some Iranian analysts said that Tehran is unlikely to push its feud with Ottawa too far, as Canada is a major place of residence for Iranian expatriates. "Iran has a humanitarian concern in this case," said Heshmatollah Falahatpisheh, a professor of politics in Tehran's Allameh University.