Medical and sea rescue NGOs operating in the Mediterranean on Sunday requested that the European Union find a safe port for a vessel carrying 141 people that had been saved from the water.

The Aquarius, a rescue vessel jointly operated by Doctors Without Borders (MSF) and SOS Méditeranée, had on Friday found 141 people adrift on two wooden boats, including at least 67 unaccompanied minors and a pregnant woman.

"Both organizations are now calling upon European governments to assign the closest place of safety without delay in accordance with International Maritime Law so that people rescued at sea can be disembarked and Aquarius can continue providing urgently needed humanitarian assistance," read a joint statement.

The NGOs assured that they had spoken with the relevant authorities in Tunisia, Malta, Libya and Italy but were unable to receive permission to dock anywhere.

The MSF doctor on board the Aquarius, David Berversluis, said he had detected several cases of malnutrition and dehydration that required continued medical treatment.

Italy's far-right interior minister, Matteo Salvini, has warned that the Aquarius will not be allowed to stop at any of his country's ports as part of his strategy to stop NGO rescue vessels from docking.

According to the International Organization for Migration, at least 3,116 people disappeared in the Mediterranean while trying to cross to Europe on board precarious vessels.