An unidentified Iranian lawmaker walks through the parliament in Tehran on Sunday, Nov. 27, 2011. Iran's parliament approved a bill to reduce Tehran's diplomatic relations with London and withdraw the British ambassador. (AP Photo/Vahid Salemi)

(Update: Iran’s Guardian Council on Monday rushed through final approval of a bill, passed a day earlier by parliament, downgrading diplomatic relations with Britain, Fars news agency reports.)

(CNSNews.com) – Just weeks after a new British ambassador arrived in Tehran following an eight-month hiatus, Iran’s parliament voted by an overwhelming margin Sunday to expel him and downgrade relations with London.

Ties between Britain and the Islamic Republic have been strained since President Mahmoud Ahmadinejad’s disputed re-election in 2009, when Iran accused the embassy of stoking anti-government protests. But the Iranian lawmakers’ demands came several days after Britain imposed new sanctions against Iran, including measures to cut any ties between British and Iranian banks.

The U.S. and Canada announced similar steps, in response to a recent report by the International Atomic Energy Agency (IAEA), which, for the first time, publicly charged Iran with developing technologies used to develop nuclear weapons. (U.S. diplomatic relations were severed in 1979; Canada has an embassy in Tehran, but has not had ambassador-level representation since 2007.)

Sunday’s vote was 179-4, with 11 abstentions. The four lawmakers voting “no” said the bill did not go far enough: They wanted a complete severing of diplomatic ties with Britain.

“It is natural that we, as representatives of the great nation of Iran and defenders of their rights, are not able to tolerate the current situation in which the U.K. ambassador is present in Tehran, and at the same time they are at the forefront of confronting national interests of Islamic Republic of Iran,” said the chairman of the parliament’s National Security and Foreign Policy Commission, Allaedeen Boroujerd, who authored the bill.

To become law, the measure must now be approved by the Guardian Council, a legal-religious body appointed by supreme leader Ayatollah Ali Khamenei.

Britain’s Foreign Office responded in a brief statement, calling the vote to expel Ambassador Dominick Chilcott “regrettable.”

“This unwarranted move will do nothing to help the regime address their growing isolation or international concerns about their nuclear program and human rights record,” a spokesman said, warning that if the government acts on the lawmakers’ call, “we will respond robustly in consultation with our international partners.”

Parliamentary speaker Ali Larijani warned of the possibility other countries could also be punished, “should they decide to behave in a manner similar to that of the British government.”

The warning was likely aimed at European countries, as European Union officials have been mulling the possibility of a ban on Iranian oil imports.

Iran’s official IRNA news agency said the British financial sanctions would have little effect: “While the experts point to the economic and social problems grappling the British government, massive student and public protests in particular, it tries to introduce itself as a main player in the international scene,” it scoffed.

Russia and China, Iran’s leading economic partners, have questioned the usefulness and legality of new Western sanctions.

“We are convinced that the sanctions track is not helpful in restoring the negotiation momentum,” Russian Foreign Ministry spokesman Alexander Lukashevich told a briefing Friday.

“On the contrary, it leads to grave consequences and puts off the possibility of Iran’s dialogue” with the international community aimed at resolving the nuclear standoff, he said.

On Sunday a delegation of Russian lawmakers arrived in Tehran for a two-day visit and meetings with senior Iranian officials, the Mehr news agency reported.