The UN's top court ordered Myanmar on Thursday to take "all measures within its power" to prevent alleged genocide against Rohingya Muslims.
The International Court of Justice granted a series of emergency steps requested by the mainly Muslim African state of The Gambia under the 1948 Genocide Convention.
Presiding judge Abdulqawi Ahmed Yusuf said Myanmar must "take all measures within its power to prevent the commission of all acts" described by the convention.
These included "killing members of the group" and "deliberately inflicting on the group conditions of life calculated to bring about its physical destruction in whole or in part."
The court based in The Hague ordered Myanmar to report back within four months, and then every six months after that.
The Gambia asked for the measures pending a full case that could take years.
The accusations refer to a 2017 military crackdown by Myanmar which resulted in around 740,000 Rohingya fleeing to Bangladesh, bringing allegations of widespread rape, arson and mass killings.