In a letter addressed to Guterres on Friday, Zarif said the plight of the Rohingya has caused international concern.

The ethnic Muslims have not only been deprived of their most basic right — i.e. the right to belong to a country and a government that would protect them — they are also being exposed to killings and violent and inhumane treatment on a daily basis, he wrote.

The Iranian foreign minister referred to an upcoming ad hoc meeting by the foreign ministers of the Organization for Islamic Cooperation (OIC) countries in Kuala Lumpur, Malaysia, on January 19 to address the situation of the Rohingya Muslims in Myanmar and said the meeting reflects the depth of concern on the part of Islamic governments about the ethnic Muslims’ conditions.

The Rohingya have been subjected to persecution in Myanmar since 2012. Extremist Buddhists have attacked the Muslims, mainly in the northern Rakhine State, recurrently, torching their houses and causing them bodily harm.

Since October last year, however, the Muslims have faced increased violence. Back then, the Myanmarese military imposed a siege on Rakhine, and the government of Myanmar has blocked humanitarian and media access to the Muslims in the state ever since. There have been numerous reports of killings, rapes, and other forms of abuse being carried out against the besieged Muslims.

Tens of thousands of the members of the minority group have been forced to flee to neighboring regions, in Kachin State or across the border to Bangladesh.

Zarif said the “the systematic violation of the Rohingya Muslims’ basic rights and denying them citizenship… and forcing them to leave their homes” would have adverse consequences on peace and stability in Myanmar as well as in neighboring and regional countries.

He said it was expected of Myanmar’s government to take immediate and effective action to protect the rights of the Rohingya and not allow extremist groups to tarnish the peaceful image of Buddhism.

The top Iranian diplomat said it is also expected of Guterres and his special envoy for Myanmar to communicate to the Myanmarese government the demand of the international community and the Islamic world concerning immediate humanitarian access to affected areas.

He also expressed hope that the UN, through the mechanisms available to it, would take the necessary measures to address the situation of the Rohingya in Myanmar.

The UN said on Friday that a special rapporteur would be visiting Myanmar on Monday to investigate reports of abuse against the ethnic Muslims in Rakhine. Special Rapporteur on Myanmar Yanghee Lee will start a 12-day visit to Rakhine and Kachin states on Monday, the UN said.

The Myanmarese army denies the allegations of mistreatment against the Rohingya. A committee set up by the government recently concluded that law was not being violated in the state, an assertion widely derided by international rights organizations.