British Prime Minister David Cameron Tuesday condemned as a "disgrace" the failure of the Iranian government to protect the British embassy in Iran from protestors, dpa reported.
Speaking after an emergency meeting of a government security committee over the issue, Cameron said the government would consider what measures to take in the next few days.
"The attack on the British Embassy in Tehran today was outrageous and indefensible. The failure of the Iranian government to defend British staff and property was a disgrace," said Cameron.
"We hold the Iranian government responsible for its unacceptable failure to protect diplomats in line with international law."
The Iranian government must immediately ensure the continued safety of embassy staff, return all property and secure the compound, said Cameron.
Earlier, Foreign Secretary William Hague warned that there would be "serious consequences" for any breach of international law by Iran.