A UN human rights envoy says severe shortages of food, water and medical care for Rohingya Muslims in western Myanmar are part of a long history of persecution against the religious minority that could amount to "crimes against humanity."

Tomás Ojea Quintana's statement follows the evacuation of hundreds of international humanitarian workers from Rakhine state, home to almost all the country's 1.3 million Rohingya, tens of thousands of whom are living in crowded displacement camps.

The aid workers left after Buddhist mobs attacked their offices and residences two weeks ago. Some have tried to return, but have been barred by the government.

Quintana said the developments in Rakhine are the latest in a "long history of discrimination and persecution against the Rohingya community which could amount to crimes against humanity."