The Biden administration is to declare that Myanmar's military has committed genocide against the Rohingya minority, US officials have said.
Secretary of State Antony Blinken is expected to make the announcement when he visits the Holocaust Museum in Washington later on Monday.
Hundreds of thousands of Rohingya Muslims have fled Myanmar since the military crackdown that began in 2017.
More than 6,000 people were killed in the first month of the onslaught.
A case against Myanmar, also called Burma, was opened at the International Court of Justice in 2019.
A civilian government was in charge when the military launched its campaign, but in 2021 the military took power in a coup.
The Rohingya, who numbered about one million in Myanmar before the attacks on them, are one of the many ethnic minorities in the country.
Rohingya Muslims represent the largest percentage of Muslims in Myanmar, with the majority living in Rakhine state.
But the government of Myanmar, a predominantly Buddhist country, denies the Rohingya citizenship and even excluded them from the 2014 census, refusing to recognise them as a people.
When US President Joe Biden took office 14 months ago, Mr Blinken pledged to conduct a fresh review of the issue.
Two previous US investigations failed to reach a conclusion.
A ruling of genocide does not automatically lead to punitive action by the US, but it is hoped it will put pressure on the Myanmar military.
"It's going to make it harder for them to commit further abuses," a senior State Department official told Reuters.
There has so far been no comment from the military authorities in Myanmar.