Myanmar must grant citizenship to the Rohingyas to allow hundreds of thousands of people from the minority to return to Rakhine State from where they were driven by an army campaign, the UN refugee chief said.

"These people cannot remain stateless because this statelessness exposes them to discrimination and abuse, as has been the case in the past," said Filippo Grandi, the UN High Commission for Refugees Thursday.

An estimated 623,000 Rohingyas have fled Rakhine State since August 25 during military operations that has included reports of burnt villages and widespread killings. The United Nations has denounced it as a classic example of ethnic cleansing.

"For people to go back and for this return to be sustainable, you need to address the very complex issue of citizenship," Grandi told reporters after addressing the Security Council, reports AFP.

"No return will be sustainable ... if that issue is not unblocked."

Filippo Grandi stressed that Rohingyas are not just refugees but stateless refugees. He added there must be reconciliation, investment and development in Rakhine, which is one of Myanmar's poorest states.

In another development, just a year after the United States lifted its sanctions against the government of Myanmar as the latter returned to democracy, Washington is considering re-imposing targeted sanctions and travel restrictions on Myanmar military officials over the treatment of Rohingyas.

The legislation is sponsored by senior lawmakers including the Republican Senate Armed Services Committee chairman John McCain, and Senator Ben Cardin, the top Democrat on the Senate Foreign Relations Committee.

The fresh move is being considered as one of the strongest efforts yet for Washington to intervene in the humanitarian crisis and introduced the day before US President Donald Trump leaves on his first trip to Asia as President.

Trump, who will spend nine days from November 5-13 visiting south-east Asia, will take him to Japan on November 5-7, South Korea on 7-8, China on 8-10, Vietnam on 10-11 and Philippines on 12-13.

In Washington, US Secretary of State Rex Tillerson announced that he will travel to Myanmar scheduled for November 15, becoming the most senior US official to visit since the start of the Rohingya crisis.

He is expected to to discuss the humanitarian crisis in Rakhine State, announced "economic options" and a "human rights law" targeting leaders involved in violence against Rohingya minority.

Tillerson previously urged Myanmar's military chief Min Aung Hlaing to help end violence in the Rakhine State and condemned the August attack by Muslim insurgents on security forces in the region.

The US legislation would bar the United States from supplying most assistance to the country's military until perpetrators of atrocities against the Rohingya are held accountable, reports Reuters.

A Rohingya child falls asleep while being carried in a basket. Photo: AFP

Yesterday, a spokesman for Myanmar's de facto leader Aung San Suu Kyi said the proposed US sanctions targeting Myanmar's military would hinder the fledgling civilian government sharing power with the generals.

Responding to the moves in Washington, Suu Kyi's spokesman, Zaw Htay, told Reuters, "We need internal stability to improve the country's economy. Imposing international sanctions directly affects the people in travel and in business investments, and there are many bad consequences."

Myanmar officials would explain the government's efforts on Rakhine during the visit of the Secretary of State, he added.

Meanwhile, a US state-department delegation, led by Acting Assistant Secretary of State for the Bureau of Population, Refugees, and Migration Simon Henshaw, is now on a four-day visit to Bangladesh and discussing the humanitarian crisis and human-rights concerns stemming from the crisis in Rakhine.

Prior to visit Bangladesh, the delegation paid a three-day visit to Myanmar from October 31.

The US delegation which also concluded a two-day visit to Rohingya refugee camps and makeshift settlements in Cox's Bazar, is scheduled to address a press conference in Dhaka this afternoon.