"No provocation can justify the horrendous atrocities that have ensued," Tillerson said after acknowledging the deadly attack on security forces by a Rohingya militia that triggered the current crisis.

"These abuses by some among the Burmese military, security forces, and local vigilantes have caused tremendous suffering. ... After a careful and thorough analysis of available facts, it is clear that the situation in northern Rakhine state constitutes ethnic cleansing against the Rohingya."

Even as State Department officials announced their decision to call the violence "ethnic cleansing," they were careful not to attribute the violence directly to Myanmar's democratically elected leadership. They also pointed out that the designation carries no specific legal consequences, though the administration is considering what other steps it could take.

"The term 'ethnic cleansing' is not defined in the context of either international law or domestic law," a senior State Department official cautioned. "However, it is a descriptive term, and it carries with it this sense of urgency."

The United States is considering additional steps it can take with other nations or unilaterally, a second senior official said, including possible targeted sanctions. More sweeping sanctions, the officials said, would not be productive.

While the Trump administration is not specifically calling out Myanmar's government for the acts of ethnic cleansing, the official said they hope it "will increase pressure on the parties to reach an accommodation about repatriation of people who are displaced, and also pressure on the military in Burma and the civilian government to work quickly to respond to events on the ground."

Tillerson's statement comes less than a week before Pope Francis is due to touch down in Myanmar for a week-long visit of the region, including a trip to Bangladesh. He called again for an official investigation into the crisis, saying those who were responsible must be held accountable.

Authorities in Buddhist-majority Myanmar have a long history of violence and oppression against the predominantly Muslim Rohingya people who live in the country's west, but in recent months the crisis has intensified.

In an exclusive CNN report released in November, refugees described the horrors they'd witnessed trying to reach the relative safety of the Bangladesh camps.

"In the pile there was someone's neck, someone's head, someone's leg. I was able to come out, I don't know how."

However, Tillerson is not the first world leader to call out Myanmar for engaging in ethnic cleansing against the Rohingya.

On Wednesday, it was announced the Pope would meet with the head of Myanmar's military as part of his visit, as well as separately with a small group of Rohingya refugees.