Bangladesh will begin relocating around 100,000 Rohingya refugees to a desolate island off its southern coast in June, a senior official said Wednesday, despite warnings the site is prone to violent weather. Authorities say shelters for around 50,000 refugees have been constructed at Bhashan Char, a silty strip of land that only emerged from the Bay of Bengal in 2006. The remaining shelters will be completed within two months, Bangladesh's disaster management secretary Shah Kamal told U.N. agencies during a briefing about the controversial plan in Dhaka.

The navy is also filling in low-lying areas and building embankments around the entire perimeter to ensure the island can resist tidal flooding and monsoon storms.

Bangladesh, a low-lying riverine country at risk from rising sea levels, is prone to tropical cyclones and 120 evacuation shelters are also being constructed on the island, Kamal said.

Nearly 700,000 Rohingya have crossed into Bangladesh since August alone, fleeing army violence in Rakhine state that U.S. and U.N. officials say amounted to ethnic cleansing. Kamal said refugees most vulnerable to the approaching monsoon would be offered the chance to relocate to the small island, which lies west of the port city of Chittagong. The process would be voluntary, he added.