U.S. Ambassador to the United Nations Nikki Haley has urged the Myanmar government to cooperate with a human rights fact-finding committee tasked with investigating allegations of army atrocities.

Myanmar has said it will deny visas to members of the mission, established by the Human Rights Council earlier this year.

The committee intends to probe accusations of abuses against the Rohingya Muslim minority in Rakhine state as well as in Kachin and northern Shan states.

"No one should face discrimination of violence because of their ethnic background or religious beliefs," said Haley in a statement circulated Tuesday.

"It is important that the Burmese government allow this fact-finding mission to do its job. The international community cannot overlook what is happening in Burma - we must stand together and call on the government to fully cooperate with this fact-finding mission."

Tens of thousands of Rohingya Muslims fled to neighboring Bangladesh following brutal "clearance operations" by the Myanmar army in October, during which hundreds of women were allegedly raped.

"The total number of victims will be unknown unless the fact-finding mission is allowed to proceed," Haley said.