Italy ordered migrants on a rescue ship off its coast quarantined on another vessel to test for the coronavirus instead of allowing disembarkation.
The Alan Kurdi, run by German non-governmental group Sea-Eye, is in international waters off the Sicilian west coast.The transport ministry said those on board will be transferred to another ship, screened by health authorities and quarantined there.
Last week government closed ports to charity ships for the duration of the national health emergency over the coronavirus, due to remain in effect until July 31.
The transport ministry statement said allowing migrants to disembark would put extra pressure on stretched health services in Sicily. It gave no details on the planned transfer, timing or location.
After a relative lull in arrivals of boat migrants from Africa, numbers picked up in the first two months of the year, only to fall back in March when Italy was hit by the epidemic.
Smaller boats with migrants continue to arrive. A dinghy carrying 100 migrants ported at Pozzallo in Sicily on Sunday, local authorities said.