TEHRAN, March 10 (Xinhua) -- Iran's Foreign Ministry summoned the British ambassador to Tehran on Saturday over the attack on the Iranian embassy in London.

"Following an assault by a number of individuals affiliated to an extremist religious group on Iran's embassy in London, the country's ambassador was summoned by the director general for European affairs," Iranian Foreign Ministry Spokesman Bahram Qasemi was quoted as saying by the state TV.

Qasemi expressed Tehran's "strong protest" over the incident and urged the British government to protect Iranian diplomats and diplomatic missions.

The British envoy in Tehran expressed his regret over the attack and said that he would inform his country of Iran's message.

On Friday, a group of four men raided the Iranian embassy in London and pulled down Iran's flag.

Local reports said they were supporters of a radical religious cult.

No one was hurt during the incident and the assailants were arrested.