Protesters broke into two British diplomatic buildings in the Iranian capital, Tehran, on Tuesday, sparking an international outcry.
A group of demonstrators managed to get through the gates of the British embassy and steal various items including a portrait of the Queen.
They burnt the Union Jack and replaced it with an Iranian flag whilst chanting ‘Death to Britain’.
A second crowd also stormed another compound in the north of the city.
France, the US and Russia – one of Iran’s closest allies – all condemned the attacks as ‘unacceptable’.
Iran has a duty to protect diplomatic staff and property under international law.
Ties have soured between Britain and Iran in recent weeks; the British government has banned banks from doing business with the Islamic Republic.
Those sanctions form part of the West’s attempt to isolate Iran, which it believes is trying to build an atomic bomb.
On Monday, the Iranian parliament voted to expel the British ambassador within the next two weeks.
The UK has vowed to respond “robustly” if that happens.