Bangladesh and Myanmar agreed on Tuesday to complete within two years the return of hundreds of thousands of Rohingya Muslims who fled an army crackdown last year in Myanmar.

United Nations Secretary-General Antonio Guterres and the U.N. Refugee Agency (UNHCR), responding to the plan, said they were concerned about forcibly repatriating over 650,000 Rohingya who fled to neighboring Bangladesh after a conflict erupted in western Rakhine state in August.

Statements from the Myanmar and Bangladesh foreign ministries said Bangladesh would set up five transit camps on its side of the border. Those camps would send Rohingya to two reception centers in Myanmar. The repatriation process would start next Tuesday, the statements said.