The British Foreign Ministry issued a statement Sunday saying it was "regrettable" that Iran's parliament approved a draft bill to downgrade diplomatic and economic relations with Britain after London increased sanctions on Tehran over its nuclear program."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," the foreign ministry said. "If the Iranian government acts on this, we will respond robustly in consultation with our international partners."RELATED:Israel watches as world rejects Iran sanctionsEU ups heat on Iran, reaches new sanctions dealIran's parliament approved a draft bill on Sunday to downgrade diplomatic and economic relations with Britain after London increased sanctions on Tehran over its nuclear program, the official IRNA news agency reported.In the 290-strong parliament, 179 voted in favor, four against and 11 abstained. The bill obliges the government to downgrade ties within two weeks, a move that would force the ambassador out and leave the British embassy to be run by a charge d'affaires.The British government, who was joined by the US and Canada, announced two weeks ago their decision to terminate all dealings with the Central Bank of Iran, a decision that covers all Iranian banks, branches and subsidiaries.“This measure will protect the UK financial sector from being unknowingly used by Iranian banks for proliferation related transactions,” said George Osborne, Britain’s treasury chief.Iran’s nuclear activities “pose a significant risk to the national interests of the UK and countries across the region,” he added. Iranian President Mahmoud Ahmadinejad said Saturday that new sanctions imposed on the Islamic Republic by the US and other western nations make the prospect of negotiations on Tehran's nuclear program "more difficult," AFP reported."They vote on resolutions, impose sanctions, use all the tools against us, and they want us to negotiate," Ahmadinejad was quoted as saying on Iranian television.Rebecca Anna Stoil contributed to this report.