Is growing a beard obligatory under Islam?

Professor Muhammad Abdel Haleem, of the School of Oriental and African Studies at the University of London, says "this is not the only view expressed by Muslim scholars."

Many Muslim scholars now do not see the beard as an obligation and do shave their beards.

Muslims learn about the Prophet's views on facial hair not from the Koran, but through hadith - or sayings - attributed to Muhammad.

One such hadith, in a collection by Muslim scholar Muhammad al-Bukhari centuries ago, stipulates: "Cut the moustaches short and leave the beard."

The Prophet Muhammad is believed to have had a beard and those who insist that devout Muslims grow beards argue that they are doing no more than asking the faithful to emulate the Prophet's actions.

The question that arises is one of enforcement.

Mr Abdel Haleem, along with many other Muslim scholars, says the wearing of beards should be considered a recommendation rather than an obligation.

The Taliban, who ruled Afghanistan until they were ousted in 2001, and the Islamists of Somalia, are among a small minority in the Muslim world who demand unconditional observance and threaten penalties for non-compliance.

Mr Abdel Haleem argues that all practising Muslims - of which he is one - should be free to exercise their choice over a matter about which there is no overall consensus of opinion, without fear of retribution.