The International Court of Justice on Thursday ordered Myanmar to take urgent measures to protect its Muslim Rohingya population from persecution and atrocities, and preserve evidence of alleged crimes against them.

Mostly Muslim Gambia launched a lawsuit in November at the United Nations' highest body for disputes between states, accusing Myanmar of genocide against Rohingya in violation of a 1948 convention.

Thursday's ruling dealt only with Gambia's request for so-called preliminary measures, the equivalent of a restraining order for states. It gave no indication of the court's final decision, which could take years to reach.

In a unanimous ruling by a panel of 17 judges, the court said Myanmar must now take all steps within its power to prevent serious harm to Rohingya, and report back within four months.

More than 730,000 Rohingya fled Myanmar after a military-led crackdown in 2017, and were forced into squalid camps across the border in Bangladesh. U.N. investigators concluded that the military campaign had been executed with "genocidal intent".

Moments before the court in The Hague began reading its ruling, the Financial Times published an article by Myanmar's civilian leader Aung San Suu Kyi in which she said war crimes may have been committed against Rohingya Muslims but that refugees had exaggerated the abuses against them.

During a week of hearings last month, Suu Kyi asked the judges to drop the case.

The World Court's rulings are final and without appeal, but it has no real way of enforcing them.

More than 100 Myanmar civil society groups published a statement saying they hoped international justice efforts would "bring forth the truth" and end impunity.

"Political and military policies have always been imposed with violent force and intimidation upon the people of Myanmar, systematically and institutionally, on the basis of their political and religious beliefs and ethnic identities and continue until the present," the statement said.

"We understand very clearly that the ICJ case against Myanmar is directed towards those responsible for using political power and military might, and not to the people of Myanmar."