Myanmar and Bangladesh have signed a memorandum of understanding for the return home of hundreds of thousands of Rohingya refugees who fled to escape a Myanmar army crackdown, according to a senior Myanmar official.

"We are ready to take them back as soon as possible after Bangladesh sends the forms back to us," said a senior official at Myanmar's ministry of labour, immigration and population.

He was referring to registration forms the Rohingya must complete with personal details before repatriation. 

Human rights groups have accused the military in mostly Buddhist Myanmar of carrying out mass rape and other atrocities during a ferocious military sweep launched in late August in retaliation for attacks by Rohingya Muslim militants in Rakhine State.

620,000 Rohingya refugees, many traumatised with gunshot wounds and burns, have fled to Bangladesh, joining hundreds of thousands who have sheltered there for years after previous periods of violence in the former Burma.

Meanwhile, the United States has temporarily suspended travel for American officials to parts of Rakhine state, the US embassy said, citing concerns over potential protests after US Secretary of State Rex Tillerson accused Myanmar of "ethnic cleansing" in the state.