Lavrov is expected to visit Banja Luka and then join the delegations in marking the 81st anniversary of the crime at the "Jasenovac" concentration camp and its largest execution site, Donja Gradina.

The government of Republika Srpska previously declared April 19 as a Day of Mourning in this Bosnian entity.

Last year, the highest delegation of the Republic of Serbia, led by President Aleksandar Vuฤiฤ‡, also attended the commemoration.