The demonstration outside the Saudi embassy in Tehran came after the toll from Thursday's stampede in Mina, outside Mecca, officially rose to 769 pilgrims. At least 155 people killed at the hajj were Iranian - more than from any other nation.

Iran's supreme leader Ayatollah Ali Khamenei demanded that Saudi Arabia apologize for the disaster, as a growing number of nations started accusing Saudi Arabia of mismanaging the mass event.

"Instead of passing the buck and playing a blame game, the Saudis should accept their responsibility and apologize to the world's Muslims and the bereaved families," he said.

Khamenei's statement came just hours after Saudi Foreign Minister Adel al-Jubeir had hit back at criticism from its regional rival, saying it "shouldn't play politics with a tragedy." Iran's State Prosecutor Ebrahim Raisi went as far as saying that Iran would sue the Saudi royal family for the tragedy.

Iranian envoy preparing to visit Saudi Arabia

Iran has been fiercely critical of the Saudi authorities' handling of safety issues during the hajj and has questioned whether the kingdom was fit to carry on organizing the annual pilgrimage.

Iran's Culture Minister Ali Jannati announced that he planned to head a delegation to Saudi Arabia to follow up on the 316 Iranians that Tehran said were missing, but the Iranian state news agency IRNA said his team had not received visas yet.

On Saturday, Tehran had summoned Saudi Arabia's charge d'affaires for the third time since the stampede, to press the kingdom for greater cooperation. But a resolution might be unlikely since animosities between the two countries run deep, as Saudi Arabia, the birthplace of Islam, and Iran back opposite warring parties in Syria and Yemen.

United Nations to mediate?

Iran's President Hassan Rouhani appealed for UN mediation with the Saudis in a meeting with Secretary General Ban Ki-moon in New York, state television reported.

"Sadly, Riyadh isn't offering enough cooperation on the missing pilgrims and the transfer of the dead and injured," it quoted Rouhani as saying.

"It is crucial that the UN remind Riyadh of its legal and humanitarian obligations."

Seeking 'political gain'

Meanwhile, Saudi media have accused Iran of trying to make political gains from the catastrophe.

The Iranians "should know better than to play politics with a tragedy," Saudi Foreign Minister Adel Al-Jubeir told reporters on Saturday.

Saudi Health Minister Khaled al-Falah suggested that the crush, which had occurred on Thursday during a stone-throwing ritual in the Saudi holy town of Mina, had resulted from pilgrims' failure to follow instructions.

Saudi King Salman bin Abdulaziz ordered a safety review in the wake of the bloodshed, which came almost two weeks after 108 people were already killed in a construction crane collapse in the Grand Mosque in the city of Mecca.

Victims from around the world

While the Saudi authorities have not yet provided a breakdown of the victims of the stampede, Iran said that 144 of its pilgrims died in the crush.

Egypt reported 55 deaths among its pilgrims. There were 29 and 22 pilgrims among the dead from India and Indonesia respectively. At least 18 Pakistanis died, while Algeria said seven of its citizens perished in the stampede.

Around 1.9 million Muslims attended this year's hajj, according to Saudi officials.

Troubled pilgrimage

The crush marked the worst disaster in the annual pilgrimage in 25 years. In 1990, 1,426 worshippers had died in a stampede inside a tunnel after the ventilation system broke down.

Seven years later, 343 pilgrims were killed in a massive fire that gutted their tents in Mina, around 10 kilometers (six miles) east of Mecca.

In 2006, 364 pilgrims were crushed to death during the symbolic stoning of the devil in Mina.

ss/gsw (AP, AFP, dpa)