Pope Francis was welcomed at Havana's Jose Marti International Airport by President Raul Castro, before being led to the Protocol Room to hold the historical meeting with Patriarch Kirill of Moscow and All Russia.
The two religious leaders will discuss the relations between the two churches, the international situations and the protection of Christians in the Middle East and North Africa under the threat of persecution and genocide. A joint statement will be issued after the meeting.
This is the first meeting between the two churches since Christianity split nearly 1,000 years ago.
Later, Pope Francis will head to Mexico for a pastoral visit while Kirill will continue his official agenda in Cuba until Sunday.