Another body was spotted off the coast of Libya on Saturday, a day after a Doctors Without Borders (MSF) rescue ship recovered the bodies of 11 migrants in the same area of the Mediterranean Sea and said it had saved more than 160 people from boats.

Non-profit organisation Sea Watch said on social media platform X that its plane had spotted the corpse on Saturday.

"Yesterday our aircraft crew sighted 11 bodies, and so far one more has been discovered on today's flight. The flight and the search continue," the Germany-based non-profit group said.

The United Nations has registered more than 20,000 deaths and disappearances in the central Mediterranean since 2014, making it the most dangerous migrant crossing in the world.

MSF said its Geo Barents search and rescue vessel picked up 146 migrants in two operations and then found a further 20 in a separate boat. They also retrieved the bodies of 11 people who were seen by the Sea Watch plane.

"We do not know the precise cause of this tragedy, but we know that people continue to die in a desperate attempt to reach safety. This slaughter must end," MSF said on X.

The 11 bodies should be transferred onto a ship of the Italian coast guard and then disembarked temporarily at the island of Lampedusa, Italian media reported on Saturday.

Italy has urged Tunisia and Libya to do more to stop would-be migrants from putting to sea. It has also clamped down on the operations of rescue ships, saying they encourage people to head to Europe - something the charities deny.

Underscoring the restrictions, Italy on Friday told Geo Barents to take its latest group of migrants to the northern port of Genova, more than 650 nautical miles away and far from the more convenient ports in nearby Sicily.

"This will significantly delay assistance for the ... survivors who endured a lot already," MSF said.