Scores of hardline Iranian university students gathered outside the fortress-like British embassy in Tehran last night to condemn Britain's "savage" suppression of a "popular uprising" against the "dictatorial royal regime of England".
Police were on hand to ensure the carefully choreographed, state-sponsored protest did not turn violent. "Death to the corrupt British monarchy", one placard trumpeted. "Royal wedding equals economic austerity," proclaimed another.
Tehran has gleefully seized on the unprecedented turmoil that convulsed Britain last week to make propaganda against London, which has rankled the Islamic republic by being a leading critic of its abysmal human-rights record.
Despite their supposed horror at the mayhem in British cities, jubilant Iranian officials made clear they have no desire to see it end.
The head of Iran's Basij street militia, Brigadier Mohammad Reza Naghdi, cheerfully predicted on Saturday that the "popular awakening" in Britain was "just the beginning" and would spread to the heart of Europe.
And a senior parliamentarian, Parviz Sorouri, opined that "the world is now coming to the conclusion that Western civilisation has no foundation and is unreal".
In the past week, Iran's authoritarian regime has teasingly offered to send human-rights observers to Britain and, even more bizarrely, to deploy male and female units of its feared Basij militia on the streets of London, Liverpool and Birmingham.
Mr Naghdi said his forces could serve as a peacekeeping buffer between "the deprived people" and "the oppressive royal regime".
The Basij, which operates under the aegis of Iran's Revolutionary Guards, spearheaded the brutal crackdown against the peaceful, mass pro-democracy protests that erupted after President Mahmoud Ahmadinejad's fiercely disputed re-election in 2009.
The Iranian regime has frequently used the "colonial old fox" Britain as a whipping boy to divert attention from its own problems. The British embassy, an oasis of green in the dusty heart of the Iranian capital, has weathered many hostile demonstrations in recent years. The mission is usually staffed by about 20 British nationals, although several are likely to be abroad on summer holidays.
Mr Ahmadinejad last week condemned the "savage crackdown" by British police on rampaging youths whom he portrayed as peaceful protesters.
He advised politicians in London to "hear the voice of the people and grant them freedoms" and urged the UN Security Council to take immediate action against London.
Parliamentarians and conservative newspapers in Tehran have variously blamed the turmoil in Britain on human-rights violations, "chronic
injustice", racism, social deprivation and the rise of student tuition fees.
London's response to the self-serving hue and cry in Tehran has been both wry and robust.
Britain's top diplomat in Tehran said on Thursday that London was happy to discuss its handling of the street unrest. But Jane Marriott, Britain's charge d'affaires, hoped that Iran would reciprocate by allowing a visit by a special UN rapporteur to investigate the "international community's grave concerns about ongoing human-rights violations within Iran". Tehran has steadfastly refused to do so.