The United Nations human rights investigator on Myanmar called on the government on Wednesday to "dismantle the system of discrimination" against the Muslim Rohingya minority and to restore their rights to citizenship and property.

Yanghee Lee, addressing the UN Human Rights Council, said conditions were not ripe for 700,000 Rohingya refugees in Bangladesh to go home and regretted that a memo of understanding on repatriation agreed this month between Myanmar and two UN aid agencies had not been made public.

She told the Human Rights Council her top priority was "constructive engagement" with Myanmar's government, which has said it will no longer co-operate with her efforts to document rights abuses.

U Myint Thu, permanent secretary of Myanmar's foreign ministry, told the forum that his government could not work with Lee, saying her assessment lacked independence, and called for her replacement.

Lee said violent sweeps by the Myanmar army in Rakhine state that prompted about 700,000 Rohingya Muslims to flee to neighboring Bangladesh "bear the hallmarks of genocide."

Rohingya database

In the meantime, the United Nations and the Bangladesh government have started formally registering hundreds of thousands of Rohingya refugees, a move that officials say would help their eventual return.

The registration programme started jointly by the UNHCR and the Bangladesh government this week is aimed at creating a reliable database of refugees living in camps on Bangladesh's southern coast, said Caroline Gluck, a UNHCR representative.

That data, expected to be ready by November, will have family and birth details of refugees, and will be shared with Myanmar, said Abul Kalam, Bangladesh's refugee relief and repatriation commissioner. "This will aid the repatriation process," Kalam said, stressing that any returns would be safe and voluntary.