The head of the United Nations' migration agency called on Thursday on Libyan authorities not to detain migrants rescued or intercepted by the country's coastguard.
The International Organisation for Migration's William Lacy Swing said he had "suggested" to Libyan representatives that they and the IOM "try to break the link" between migrants being collected from the sea and put in detention.
Migrants brought into Libya from the Mediterranean should instead be taken to a "reception centre to be returned within a few days to their home", he said at a press conference in Tripoli.
Swing added that since late November, the IOM had helped repatriate by air 35 000 migrants who had been held at detention centres in the Libyan capital.
Another 10 000 have been repatriated from Libya by land via Agadez in Niger.
A November summit in Abidjan saw the creation of a working group composed of the European Union, African Union, the IOM and the UN's refugee agency UNHCR.
The group aimed to speed up the evacuation of thousands of migrants in response to outrage caused by media images of a slave market in Libya.
During dictator Muammar Gaddafi's rule, thousands of migrants crossed Libya's 5 000km of southern land borders in attempts to reach the Mediterranean and cross to Europe.
The flow of migrants through Libya surged after Gaddafi was toppled and killed in 2011, with smugglers exploiting the country's chaos to send tens of thousands of people each year across a 300km stretch of the Mediterranean to Italy.
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