DUBAI - Iran considers dual nationals aboard a Ukrainian plane that was shot down accidentally this month to be Iranian citizens, the Foreign Ministry spokesman said on Monday.Iran does not recognize dual nationality. Many of the 176 people killed in the disaster were Iranians with dual citizenship. Canada had 57 citizens on board."We have informed Canada that Tehran considers dual nationals who were killed in the plane crash as Iranian citizens ... Iran is mourning their deaths," Foreign Ministry spokesman Abbas Mousavi told a televised weekly news conference.As protests erupted in Iran over the plane disaster, the British ambassador in Tehran was briefly detained. Officials said he was at an "illegal" rally, while the envoy said he was attending a vigil for victims. Britain criticized his detention."Iran respects all foreign diplomats in Iran as long as they do not violate international laws," Mousavi said.