Global aid groups on Saturday warned Myanmar they would boycott any new camps for Rohingya returnees to Rakhine state, saying refugees must be allowed to settle in their original homes.
The joint statement, signed by more than a dozen humanitarian organisations including Save the Children and Oxfam, said the groups were "concerned" by recent announcements that Myanmar would begin repatriating Rohingya refugees from Bangladesh in two months.
More than 626,000 of the ethnic minority have fled into Cox's Bazar since late August, when the Myanmar army launched a sweeping crackdown on Rohingya rebels in northern Rakhine state.
After inking a repatriation deal with Myanmar in November, Bangladesh said returnees would initially live in temporary shelters in Rakhine state.
That announcement raised fears that the refugees would face a repeat of the situation endured by more than 100,000 Rohingya in central Rakhine, who have been trapped in squalid camps ever since they were displaced by a 2012 outbreak of violence.
"There should be no form of closed camps or camp-like settlements. INGOs will not operate in such camps if they are created," aid groups said Saturday, adding that all returns must be voluntary.
The UN has said the army campaign, which saw hundreds of Rohingya villages razed to the ground, likely amounts to ethnic cleansing and has possible "elements of genocide," charges Myanmar vehemently denies.
While the worst bouts of violence appear to have subsided in recent months, refugees are still crossing the border, UNHCR said on Friday, insisting that peace must be secured before any repatriation process begins.
The Rohingya face intense discrimination in mainly Buddhist Myanmar.
Myanmar does not recognise the minority as a genuine ethnicity and has systematically stripped the group of citizenship, while curtailing their movement and access to jobs and basic services.
Authorities have also severely curbed aid access to northern Rakhine since the violence erupted in late August, a blockade that has helped drive more refugees across the border.