By politics.co.uk staff
British rhetoric against Iran has stepped up a gear, with David Miliband saying the regime faced a "crisis of credibility".
"No one is seeking regime change in Iran from the outside world," the foreign secretary said, referring to allegations from Iranian authorities that the unrest is the result of British and American interference.
"The truth is that there is a crisis of credibility between the Iranian government and their own people. It is not a crisis between Iran and America or Iran and Britain, however much the Iranian government want to suggest that.
"The people on the streets are there because of the crisis of credibility of the election results that were announced. That is not a British motivation, that is an issue for the Iranian people to decide."
Earlier this week Britain and Iran engaged in tit-for-tat expulsion of diplomats.
Meanwhile, consular staff in the British embassy in Tehran are looking into the possible detention of a British citizen of mixed race Greek origin, called Jason Fowden.
A contributor to the Guardian, his parents released a statement calling for his release.
"His work serves no purpose other than the fair and humane coverage of life in the many countries where he has worked. He has a particular love of Iran, and a deep respect for its cultural and religious traditions," the family said.
Authorities have severely hindered attempts by international media to cover the demonstrations, forcing most news outlets to rely on user generated content, such as mobile phone footage and Twitter accounts.