The UN has called on Myanmar to end the ongoing violence against Rohingya Muslims in the majority-Buddhist country.
Secretary General Antonio Guterres said the situation in the country’s western Rakhine state was best described as ethnic cleansing.
“When one-third of the Rohingya population had to flee the country, could you find a better word to describe it?” he said.
Thousands of Rohingya Muslims have fled to Bangladesh from Myanmar since 25 August.
The violence started after Rohingya insurgents attacked police posts and an army camp in Myanmar.
The attacks led to a sweeping military counter-offensive by Myanmar security forces, displacing around 400,000 people and leaving aid camps in Bangladesh struggling to cope with the influx.
“The humanitarian situation is catastrophic,” said Mr Guterres. “This is a dramatic tragedy. People are dying and suffering in horrible numbers and we need to stop it.
“I call on the Myanmar authorities to suspend military action, end the violence, uphold the rule of law, and recognise the right of return of all those who had to leave the country.”
Mr Guterres said he had spoken with Myanmar’s leader Aung Suu Kyi, who has been internationally criticised for not taking action to protect the Rohingyas.
Ms Suu Kyi was due to attend the UN General Assembly in New York next week, but has cancelled her visit to deal with the crisis.
At the request of the UK and Sweden the UN Security Council also met on Wednesday to discuss the crisis and publicly condemned the situation in Myanmar, formerly known as Burma.
The 15-member council “expressed concern about reports of excessive violence” and called for immediate action to protect civilians and resolve the refugee problem.
The statement is the first time the Security Council has commented on Myanmar in nine years, according to British Ambassador to the UN Matthew Rycroft.
Statements by the council have to be unanimously agreed and traditionally Russia and China have protected Myanmar from censure.
Last week, Myanmar said it was negotiating with Russia and China to block any statements from the council, but both countries supported Wednesday’s condemnation of the violence.
(c) Sky News 2017: UN says Myanmar violence is ethnic cleansing as Rohingya exodus continues