A protester has climbed onto the balcony of the Iranian Embassy in central London. The Metropolitan Police said additional officers have been sent to the scene in Kensington, where a number of people have gathered. Social media footage appeared to show a man on the balcony pulling down the flag and replacing it with the pre-Islamic revolution lion and sun flag – often used by Opposition groups in the country.

Protests in Iran began on December 28 and have transformed into the most significant challenge to the regime for several years. Earlier this week, Sir Keir Starmer condemned the killing of protesters in the country and urged Tehran to “exercise restraint” amid a crackdown on demonstrations against the regime.

At least 62 people are reported to have been killed and 2,300 detained during weeks of protests initially sparked by anger over the country’s ailing economy.

Iran’s leaders have also shut down access to the internet and international telephone calls in response to the protests.

The Iranian Embassy was the site of a famous siege in 1980 when six armed men took 26 people hostage.

The hostage-takers were Iranian-Arabs campaigning for the sovereignty of Khuzestan, a province in the south-west of the country.

SAS soldiers stormed the Embassy in 17 minutes on day six of the siege. They rescued all but one of the hostages, killing five of the six hostage-takers in the process.