He has called on western powers to tone down their bellicose rhetoric and in the past has suggested that Iran should be allowed to enrich small amounts of uranium.

ECONOMIST: Iran's president visits New York

Magnus Ranstorp, a terrorism specialist at St Andrew's University, believes western governments may have made a mistake in focusing their rhetoric too much on Mr bin Laden, instead of stressing that he heads a large, intricate network which will not disappear instantly, even if he and his immediate comrades are killed or neutralised.

ECONOMIST: The al-Qaeda network