Iran's supreme leader, Ayatollah Ali Khamenei, has intervened to head off a major row between the two main factions of the clerical regime over a controversial student play.

Hardliners had condemned the play as blasphemy, but at Friday prayers in Teheran, the Ayatollah called on the factions to unite.

The affair of the student play had become the latest bone of contention in the increasingly heated struggle between hardline conservatives and reformist moderates.

Published in an obscure and minor student magazine, the play was seized on by hardliners as evidence that the Ministry of Culture, which is largely in the hands of moderates, was encouraging a dangerous climate of permissiveness.

Affront to the faith

Friday Prayers are one of the Ayatollah's main platforms

The play appeared to mock the notion central to the Shia Muslim faith that the 12th Imam will one day return to preside over a new era of justice.

A leading right-wing cleric called for the student authors to be put to death. Angry demonstrators threatened to take the law into their own hands.

But speaking at Friday prayers, Ayatollah Khamenei, from whom the hardliners generally take their lead, issued a clear edict banning any such vigilante action against the two students.

He said it was for the authorities alone to investigate the case and to decide what punishment - if any - would be appropriate.

At the same time though he called on those in charge of culture to review their policies and to correct any faults.

Elections approaching

He warned the political factions not to exploit the affair and urged them to close ranks in a display of unity that would isolate the real enemies of the Islamic regime.

The Ayatollah's call for reconciliation came against a background of rising political tension with the approach early next year of parliamentary elections.