The OSCE's chairman in office has started a tour of the South Caucasus with a visit to Azerbaijan.
Didier Burkhalter, who is also the Swiss foreign minister, arrived in Baku on June 1.
Burkhalter is due to hold talks with Azerbaijani President Ilham Aliyev on June 2.
Burkhalter is also expected to meet with other Azerbaijani officials and civil society groups.
On June 3, Burkhalter will visit Georgia. His tour of the region will end on June 4 with a visit to the Armenian capital, Yerevan.
Issues related to the breakaway regions of Nagorno-Karabakh, Abkhazia, and South Ossetia are expected to top the agenda of talks in all three states.
With reporting by apa.az and armradio.am