LONDON, Nov. 30 (UPI) -- Britain evacuated its diplomatic staff from Tehran Wednesday and expelled Iranian diplomats in London after protesters stormed the British Embassy in Tehran.
The Foreign Office in London said in a statement authorities believed "the safety of our staff and their families is our immediate priority. In light of yesterday's events and to ensure their ongoing safety, some staff are leaving Tehran."
Iranian protesters stormed the embassy grounds and the nearby diplomatic residence Tuesday, tore down a British flag, broke windows, defaced walls and pictures of Queen Elizabeth II, and briefly held six staffers.
British Foreign Secretary William Hague expressed outrage over the attack, saying Britain held Iran's government responsible and promised "other, further, and serious consequences," The New York Times reported.
Hague said Britain gave the Iranian ambassador in London and his embassy staff 48 hours to leave the country, The Washington Post reported.
"If any country makes it impossible to operate on their soil they cannot expect to have a functioning embassy here," Hague said.
Norway temporarily closed its embassy in Tehran but has not withdrawn diplomatic personnel, the Times reported. A spokeswoman said the Norwegian authorities took the action after the attack on the British facilities.
European ambassadors in Tehran met Wednesday to discuss options in light of the attack, one European diplomat told the Post.
The scale of Tuesday's protest and attack by hundreds of students seemed to catch some Iranian officials off-guard and prompted Iran's Foreign Ministry to release an expression of regret.
The attacks came after Britain imposed new sanctions against Iran, including cutting ties with Iran's Central Bank. The United States and the European Union last week also imposed a new round of sanctions after a United Nations report said evidence suggested Iran may be developing nuclear weapons and missile delivery systems.
The Times reported footage played on state television showed police standing around as the protesters stormed the British compound and only began intervening after the attack was well under way.
Hague on Tuesday said it was "fanciful" to think the attack on the British Embassy could have happened without the implicit blessing of the Iranian government, the Post said.
The British minister said London would not cut all diplomatic ties with Iran and the two nations would continue to keep some lines of communication open for issues such as Iran's nuclear program and human rights.
One ambassador who visited the British Embassy grounds to search for the British ambassadors' dog, which was found, said the damage was extreme, the Post reported.
"The place had been systematically ransacked, paintings were destroyed and furniture was broken," the diplomat said. "We have concluded that the attack had been extremely well coordinated by the authorities."
The official Iranian English-language TV channel broadcast the entire assault on the British Embassy, which Western diplomats said was led by paramilitary Basij brigades controlled by Iran's Revolutionary Guards and loyal to Iranian Supreme Leader Ayatollah Ali Khamenei.
The United States, France, European Union and U.N. Security Council also condemned the assault. Russia, Iran's closest ally, described it as "unacceptable and deserving condemnation."