Britain, or the "Little Satan" as the country has been branded by Iran's leaders, has been the focus of much Iranian wrath since the beginnings of the protests.
Khamenei labeled the country the "most treacherous" of all Western powers, politicians and state media have accused Britain of malicious interference, and the BBC's correspondent Jon Leyne has been expelled.
And Reuters is reporting today that an Iranian parliamentarian said that Tehran would temporarily recall its ambassador to Britain.
An embassy siege would be a useful distraction for the Iranian regime. Where the opposition has martyrs like Neda to rally around, pro-regime forces could be drawn to the galvanizing allure of a second "nest of spies."
Britain is a useful scapegoat for the Iranian regime. In the popular mindset, because of its dubious colonial role in Persia, Britain is enemy No. 1. The regime is now just doing what it has always done, opportunistically tapping into that general antipathy.
As Simon Tisdall writes in yesterday's "Guardian":
Iran's obsession with specifically British interference has a long history, dating back to the Napoleonic era, and is to some degree justified. At that time London pledged military and other assistance in return for Iran's help in keeping imperial Russia out of British India. But as Ali Ansari relates in his book, Confronting Iran, repeated British double-crosses, acts of bad faith, and shameless exploitation of Iran's resources, convinced Iranians that while the Russians were bullies, "the British were duplicitous at best".
And because of the passing of time, like the best villains, Britain is a murky, amorphous enemy, its transgressions loom large in the collective consciousness, whereas the details do not.
Because of the weight and resonance of history, there is no need for the Iranian regime to produce any evidence of Britain's supposed nefarious role -- no need for seizures of arms caches, or parading spies on television. History alone vindicates the accusations. It's the gift that just keeps on giving.
(This tendency to blame the Brits for everything was lampooned in a popular Iranian novel from the 1970s, "My Uncle Napoleon.")
Blaming the Brits might also be calculation on the part of the regime to not damage relations with the United States.
Avenues with the Americans remain open, the Brits are reminded once again of their shameful imperial past, and supporters of the regime can galvanize popular opinion by blaming it all on the bad old fox.
With a fantasy this good, is doesn't matter how ludicrous the accusations.
As one wag, commenting on a "Times" story, wrote, "Why do the Iranians think that the UK has been instrumental in organising these protests? The British Government has done nothing successfully for years!"
-- Luke Allnutt