Official reports say at least 39 people have died when two boats sank off Tunisia while they were trying to reach Europe, in the latest disaster in the Mediterranean sea.

All the deceased were from sub-Saharan African countries, Mohamed Zekri, spokesman for Tunisia's defence ministry, said on Tuesday.

The coastguard rescued 165 other people who were on board the boats heading to the Italian island of Lampedusa, he added. Search for more survivors was on off the coast of the port city of Sfax.

The coastline near Sfax has become a main departure point for people fleeing conflict, persecution and poverty in Africa and the Middle East and seeking a better life in Europe.

In 2019, about 90 people from African nations drowned when their boat capsized off the Tunisian coast after setting off for Europe from neighbouring Libya.

Between January 1 and February 21, some 3,800 people arrived in Italy by sea, including nearly 1,000 via Tunisia and 2,500 via neighbouring Libya, according to the United Nations' refugee agency.

In February, 22 people of various African nationalities who departed Sidi Mansour, near Sfax, disappeared at sea, while 25 were rescued by the Tunisian navy about 100km (62 miles) from Lampedusa. One body was retrieved.

The International Organization for Migration says over 20,000 people have died in the Mediterranean since 2014.

(With input from agencies)