A large number of protesters gather in front of riot police as they prepare to break in to the British Embassy during an anti-British demonstration in the Iranian capital on November 29, 2011 in Tehran, Iran. Relations between the two countries have soured further over recent weeks, with the UK Treasury imposing sanctions on Iranian banks, accusing them of supporting the country's nuclear programme. The Iranian authorities insist that its nuclear plans are for peaceful purposes only and parliament has voted to downgrade diplomatic relations with the UK. (Photo by FarsNews/Getty Images)