A UN human rights investigator urged Bangladesh on Thursday to allow a safety assessment of the remote island where the government shipped 1,600 Rohingya refugees last week, and a verification process to ensure that refugees are not forced to go.

The UN says it has not been allowed to carry out a technical and safety assessment of Bhasan Char, a flood-prone island in the Bay of Bengal, and was not involved in the transfer of refugees there.

Thomas Andrews, the UN human rights investigator to Myanmar, said the assessment process were in the “best interest of all”. “They will assure the government of Bangladesh of the suitability of Bhasan Char.”