The shows a structure being constructed on Bhashan Char island off the Bangladeshi coast, as it is being prepared for the relocation of Rohingya refugees after fleeing violence in neighboring Myanmar. (AFP)

A UN envoy on Thursday offered technical expertise to Bangladesh to assess arrangements on an island where the South Asian country plans to shift about 100,000 Rohingya refugees.

Kelly Clements, a deputy high commissioner of the UNHCR, told reporters in Dhaka that the UN wanted to be “engaged” in the proposed refugee relocation, which has been criticized by rights groups.

“We have offered and told the government that we’d like to be engaged and understand better their plans. We have offered our technical experts to come… and assess and see what arrangements have been made,” she said.

Nearly a million Rohingya, including some 740,000 who fled a 2017 military crackdown in Myanmar’s Rakhine state, are now living in squalid camps in Cox’s Bazar, southeastern Bangladesh.

Bangladesh has constructed facilities for some 100,000 people on Bhashan Char, an island in the cyclone-prone coastal belt, and says it is ready to shift the refugees from the crowded settlements.

But aid agencies and rights groups have opposed the idea.

Bangladesh has recently been erecting barbed-wire fences around the Cox’s Bazaar camps, a move that the Human Rights Watch (HRW) compared with building an “open air prison”.

Clements said the fencing “is not always the best answer in terms of security.”

“Obviously we’ll try to see how it can be implemented in a way that doesn’t adversely affect the refugee community nor the host,” she said.

In a reply to a question on the refugees’ chances of repatriation, she said it would be “extremely difficult to set a timeline”.