Myanmar troops want Rohingya to leave border region, drawing sharp response from Bangladesh which hosts most refugees.
Myanmar on Friday defended deployment of its troops near the Bangladesh border, where thousands of Rohingya refugees have taken shelter, calling it an "anti-terrorism operation".
The move has drawn criticism from Bangladesh, which summoned Myanmar's ambassador on Thursday, while the UN refugee agency raised their concerns at the military build-up.
Some 200 troops were deployed to the border on Thursday, close to a nearby strip of land between Myanmar and Bangladesh that is home to makeshift camps housing some 6,000 Rohingya refugees.
The strip of land is officially designated as Myanmar territory but is widely referred to as "no man's land" because it lies beyond the country's border fence.
"We acted this way based on the information we got regarding terrorism, especially the Arakan Rohingya Solidarity Army (ARSA) movement," Zaw Htay, a spokesperson for the Myanmar government, told AFP news agency on Friday.
"It was not aimed at antagonising Bangladesh," Htay said.
Bangladesh has called for an immediate pullback of Myanmar security forces - who have reportedly issued warnings using loudspeakers for Rohingya to leave the "no man's land" - from the area.
Nearly 700,000 Rohingya have fled Myanmar since August following a government crackdown, which was launched in the wake of deadly attacks on military posts by the ARSA.
It is the fastest growing refugee crisis in the world, according to the United Nations, with the majority of the displaced seeking refuge in neighbouring Bangladesh.
The Rohingya, one of the most persecuted communities in the world, are not recognised as citizens of Myanmar and face widespread discrimination from the authorities. Prior to the current exodus, tens of thousands of Rohingya have already been living as refugees in several neighbouring countries.
The prospects for repatriation
Myanmar and Bangladesh announced a repatriation deal in January, but rights groups and Rohingya have raised concerns about the agreement, saying it does not guarantee full citizenship, or safety, for those who return.
Filippo Grandi, the UN high commissioner for refugees, said last month conditions in Myanmar are "not yet conducive" for the Rohingya to go back.
"The causes of their flight have not been addressed, and we have yet to see substantive progress on addressing the exclusion and denial of rights that has deepened over the last decades, rooted in their lack of citizenship," Grandi told the UN Security Council on February 13.
Rights group Amnesty International said last month Myanmar's history of discrimination and segregation of the Rohingya were early "warning signs" of the ongoing crisis.
"This episode will stand in history as yet another testament to the world's catastrophic failure to address conditions that provide fertile ground for mass atrocity crimes," Secretary-General Salil Shetty said on February 22.
"The transformation of discrimination and demonisation into mass violence is tragically familiar, and its ruinous consequences cannot be easily undone," he added.
The UN has said the abuses by Myanmar's military may amount to genocide.