The United Nations on Tuesday called on Israel to scrap a new program aiming to decrease the number of African infiltrators in the country, condemning it as incoherent and unsafe.
The program targets an estimated 38,000 infiltrators, mainly from Eritrea and Sudan.
Israel has offered them $3,500 (2,900 euros) and a plane ticket if they leave by March, warning they may face arrest after the deadline.
The UN refugee agency sounded a fresh alarm against the plan, first unveiled last year, after Prime Minister Binyamin Netanyahu's announcement last week that the program had begun to be implemented.
"UNHCR is again appealing to Israel to halt its policy of relocating Eritreans and Sudanese to sub-Saharan Africa", the agency said in a statement.
UNHCR spokesman William Spindler told reporters in Geneva that the program was not "coherent" and "has been implemented not in a very transparent manner."
Israel has not clearly said where the infiltrators will go, but tacitly recognizes it is too dangerous to return the Sudanese and Eritreans home.
As a result, according to activists in Israel, it has signed deals with Rwanda and Uganda, which agree to accept departing infiltrators on condition they consent to the arrangement.
Uganda has publicly denied any such deal. Rwanda has also dismissed its involvement, according to the UN.
Spindler said the fact that the purported host countries were denying their role made it impossible for the UN to follow up.
UNHCR said it had spoken to 80 people who were flown with the $3,500 to Rwanda before heading north, traveling to Rome through conflict zones in South Sudan, Sudan and Libya.
"Along the way they suffered abuse, torture and extortion before risking their lives once again by crossing the Mediterranean to Italy", UNHCR said in a statement, explaining that its staff interviewed the migrants in Rome.
Spindler called on Israel to find alternative solutions to the problem “in line with international standards,” stressing that the UN was ready to help with formal resettlement.