According to Islamic teachings, the hajj is the annual manifestation of Muslim unity. This is a common theme among Muslim scholars when describing the scene of millions of Muslim worshipers from around the world, all wearing plain white robes and performing the same rituals, despite their ethnic and sectarian differences. This grand, symbolic gesture of Islamic unity seems to be reeling under the effect of politics, in particular the row between the two dominant Islamic states in the Middle East, Saudi Arabia and Iran, which since 2012 appear to be engaged in an undeclared state of regional war.

The two countries opened a new chapter in their already tense relations Sept. 5 when Iran’s supreme leader, Ayatollah Ali Khamenei, launched one of the harshest verbal attacks on the government of Saudi Arabia since being chosen to succeed Ayatollah Ruhollah Khomeini in 1989. In his annual hajj message, Khamenei recalled the stampede during last year’s hajj that led to a reported 2,000 people being killed, among them 472 Iranians.

“The heartless and murderous Saudis locked up the injured with the dead in containers — instead of providing medical treatment and helping them or at least quenching their thirst. They murdered them.” Khamenei called Saudi rulers “disgraced and misguided” and referred to Saudi muftis as “impious and haram eating … who blatantly issue fatwas against the Book and Sunnah.” Khamenei said those who accuse Iran of preventing its citizens from making the hajj are “media minions” of Saudi Arabia and reporting lies. Khamenei added that Muslims should “reconsider the management” of the annual pilgrimage.

“The Saudi-Iranian tension is dangerous and takes the conflict to the edge of the abyss,” said former Saudi diplomat Abdullah Shammari in an interview with Al-Monitor. Shammari, an expert on Iranian and Turkish affairs, accused Tehran of starting the row by interfering in Saudi affairs, referring to Tehran’s reaction to the execution of dissident Saudi Shiite cleric Sheikh Nimr al-Nimr earlier this year. Protesters then attacked Saudi diplomatic compounds in Tehran and Mashhad.