Joint International Commission for Theological Dialogue between the Catholic Church and the Oriental Orthodox Churches

The division between the Oriental Orthodox Churches and the Catholic Church can be traced to the years following the Council of Chalcedon (451) whose Christological teaching the Oriental Orthodox did not accept. Attempts were made to reconcile with some of the Oriental Orthodox Churches at the Council of Florence (1438–1445), but none of these provided a lasting solution.

Source: Wikipedia — Joint International Commission for Theological Dialogue between the Catholic Church and the Oriental Orthodox Churches (CC BY-SA 4.0)