A senior Iranian cleric has taken the Organization of the Islamic Conference (OIC) to task for its inaction over the ongoing crisis in northern Yemen.

Delivering an address as Tehran's interim Friday Prayers leader, Ayatollah Ahmad Jannati said "certain Islamic countries have formed an alliance with the Yemeni government to crack down on the Shia population of Sa'ada Province."

Ayatollah Jannati charged Saudi Arabia with sending aircraft to the Yemeni army and shelling the Shia-populated region of Sa'ada.

He went on to describe the Saudi operations against the Houthis tribal group in Yemen as a campaign by Wahhabis to exterminate Shias.

Yemen has been fighting a war in its northern mountains near the border with Saudi Arabia against a Shia tribal group known as the Houthis, which has resulted in a humanitarian crisis in the region.

Tens of thousands of people have been displaced by the fighting and shelling while hundreds have been killed and wounded in the clashes.

The government accuses the Houthis of seeking to restore a religious leadership, which ended in a republican coup in 1962, as well as violating the terms of an armistice by taking foreign visitors hostage in 2009.

The Houthis say they demand an end to social, economic and political 'discrimination' against Shias in Yemen as well as Saudi-backed attempts to spread Wahhabism - a sect that preaches controversial and violent actions - in the north and accuse the government of widespread corruption.

Expressing concern about the current Yemeni crisis, Jannati questioned the efficiency of the OIC, calling on the establishment for quick action on the matter.

CS/HGH