Washington has announced it is pushing for targeted sanctions against Myanmar officers involved in violence against Rohingya Muslims, while withdrawing invitations to senior members of the security forces to visit the United States and ending travel waivers.
The move came after secretary of state Rex Tillerson said the US holds Myanmar's military leadership "accountable" for the Rohingya refugee crisis, drawing a distinction with Aung San Suu Kyi's civilian government.
More than 600,000 members of the minority Muslim group have fled across the border into Bangladesh in an intensifying crisis that began in late August.
Militant attacks on Myanmar security forces in the country's northern Rakhine state sparked a major army crackdown on Rohingya, who are labelled illegal Bengali immigrants by much of the rest of the Myanmar population.
_______________
Read more:
[ Nations pledge $335 million to Rohingya refugees ]
[ Rohingya tragedy 'unforgivable', Queen Rania says after visiting refugee camps ]
_______________
"We express our gravest concern with recent events in Rakhine state and the violent, traumatic abuses Rohingya and other communities have endured," state department spokeswoman Heather Nauert said on Monday, announcing a raft of measures.
"It is imperative that any individuals or entities responsible for atrocities, including non-state actors and vigilantes, be held accountable."
The state department was "assessing authorities... to consider economic options available to target individuals associated with atrocities", Ms Nauert added.
She said the US had halted its consideration of travel waivers for senior Myanmar military leaders, and was weighing targeted individuals under the Global Magnitsky Act.
The measure allows the US executive branch to impose visa bans and sanctions on individuals anywhere in the world responsible for committing human rights violations.
"We are consulting with allies and partners on accountability options at the UN, the UN Human Rights Council, and other appropriate venues," Ms Nauert said.
America has also rescinded invitations to senior members of Myanmar's security forces to US-sponsored events and is pressing for "unhindered access" to the affected areas of Myanmar for a United Nations fact-finding mission, international organisations and the media.
Mr Tillerson warned last week that the world would not stand and "be witness to the atrocities that have been reported", adding that the military must be disciplined and "restrained".
Myanmar's army chief, Min Aung Hlaing, defended his forces on Tuesday.
"One-sided statements and accusations against Myanmar and security members over the terror attacks of extremist Bengalis in the west of Rakhine State are totally untrue," he said in a post on his Facebook page.
Supporters say Rohingya have been systematically deprived of basic rights over decades in majority Buddhist Myanmar.
In the latest crackdown, Myanmar's security forces have fired indiscriminately on unarmed civilians, including children, and committed widespread sexual violence, according to UN investigators.
