The leader of the breakaway Turkish Cypriots on ethnically divided Cyprus has decried a new law making the annual commemoration of a 1950 plebiscite in support of union with Greece mandatory in Greek Cypriot schools.

Mustafa Akinci on Saturday called the move a "serious blow" to ongoing talks aimed at reunifying the island.

Akinci called on Greek Cypriot President Nicos Anastasiades to publicly denounce the law. He also urged two biggest Greek Cypriot political parties — right-wing DISY and communist AKEL, which back reunification efforts — to rescind it in parliament.

Cyprus' parliament on Friday approved the law — proposed by the far-right ELAM party — despite AKEL voting against and DISY abstaining.

Cyprus was divided in 1974 when Turkey invaded after a coup aiming at union with Greece.