The storming of British Embassy compounds by Iranian protesters complicates the search for a negotiated solution to the standoff over Tehran's nuclear programme, and appears to reflect infighting among Iranian factions. <br /><br />UK's prime minister David Cameron has warned Iran of serious consequences following what Britain has labelled an outrageous and irresponsible attack.<br /><br />Britain has been at the forefront of the international campaign for tougher sanctions against Iran over its nuclear programme, which Britain and other Western countries suspect is aimed at developing a nuclear weapon but Tehran insists is peaceful. <br /><br />Al Jazeera's Dorsa Jabari reports from Tehran.
