Crown Prince Nayef, the new heir to Saudi Arabia's King Abdullah, warned that the kingdom would use 'all means' to ensure a peaceful Haj pilgrimage amid tumult in other Arab countries and rising tensions with Iran.

Millions of Muslims have started to arrive in the holy city of Makkah to perform the Haj, one of Islam's five pillars and a duty for all Muslims who are physically able.

Home to Islam's holiest sites, Saudi Arabia regards itself as the guardian of Islam and assumes the responsibility of maintaining a peaceful Haj when Muslims from many countries and sects gather at the same place and time.

'We are ready to face all events, whatever they are ... our means are peaceful ... except for those who want to attack, whom we will prevent with all means,' Nayef told a news conference in Makkah in answer to a question about the possibility of violent protests. Nayef is also Saudi Arabia's interior minister.

The news conference followed a military parade featuring riot police, special forces and tanks that the kingdom can call upon in the event of trouble hitting the pilgrimage.

In 1987 clashes between Iranian pilgrims and Saudi security forces led to the deaths of hundreds of people. Last month the interior ministry accused an unnamed foreign power, widely interpreted as meaning Iran, of instigating an armed attack by members of the kingdom's Shi'ite minority on a police station, injuring 11 security officers and three civilians.

Later in October, the US accused two Iranians of plotting to assassinate the Saudi ambassador to Washington with the backing of Tehran. Iran denied the charges. - Reuters