Council of Blachernae (1285)

The Council of Blachernae was convened in 1285 in the Blachernae Palace in Constantinople. Under the presidency of the Patriarch of Constantinople, Gregory II, the Greek Orthodox Patriarch of Alexandria Athanasius III, and Emperor Andronikos II Palaiologos, the council repudiated the Union of the Churches under the Council of Lyons (1274), and condemned the pro-Unionist patriarch John XI Bekkos.

...
Wikipedia