President Niyazov has built a personality cult around him

But in Turkmenistan, knowledge of the highway code and control of the steering wheel are no longer enough.

Candidates now have to pass an exam in President Niyazov's spiritual writings, contained in a book named the Ruhnama.

"The exam in the Ruhnama is needed to educate future drivers in the high moral principles of Turkmen society," an official told the AFP news agency.

Mr Niyazov, Turkmenistan's "president for life" whom correspondents say is at the focus of a flourishing personality cult, wrote the Ruhnama as a moral guide to his six million people.

The semi-philosophical code is aimed at promoting a spirit of national consciousness among Turkmens.

A copy of the Ruhnama is placed in mosques alongside the Koran, so worshippers can touch it on their way inside.

Excerpts are displayed on billboards, and the book dominates state institutions, media and the arts. It is required reading in both school and university curricula.

Mr Niyazov, known generally as Turkmenbashi or Leader of the Turkmens, has grown increasingly eccentric in recent years, analysts say.

In 2002 he renamed some calendar months after himself and his mother.

This year he has made several edicts about personal appearance.

In February, he criticised long hair and beards among young men, and in April he urged Turkmens to resist the fashion for gold-capped teeth.