Les tensions entre orthodoxes et protestants sont apparues au grand jour en 1998, à la veille de la Huitième Assemblée du COE, quand les Eglises orthodoxes de Bulgarie et de Géorgie se sont retirées de cette organisation et que la famille orthodoxe, dans une déclaration faite en mai 1998 à Thessalonique, a exprimé son mécontentement devant la situation actuelle.

Dans cette déclaration, les Eglises orthodoxes mettaient l’accent sur leur longue tradition oecuménique et leur solide engagement au sein du COE, mais elles d éploraient le fait que les structures actuelles du Conseil oecuménique rendent difficile une participation adéquate des orthodoxes. La déclaration formulait également d’autres critiques, touchant notamment la stagnation " dans les discussions théologiques multilatérales entre chrétiens ", le langage liturgique utilisé au COE, ainsi que les questions de l’ordination de la femme et de l’orientation sexuelle.

En raison des différends qui avaient surgi, il avait été décidé en décembre 1998, à la Huitième Assembl ée de Harare, de créer une commission mixte composée d’orthodoxes et de protestants, afin d’examiner les critiques des orthodoxes et d’ élaborer des solutions possibles.

Sur les 337 Eglises membres que compte actuellement le COE, 21 sont orthodoxes. Celles-ci représentent numériquement plus du tiers des chrétiens appartenant aux Eglises membres du COE. L'Eglise orthodoxe russe est la plus grande Eglise membre du COE.

Participants à la réunion de Morges (au 3 décembre 1999) :

• Dr Anna Marie Aagaard, Evangelical Lutheran Church in Denmark, Denmark
• Very Rev. Nareg (Manoug) Alemezian, Armenian Apostolic Church (Cilicia), Lebanon
• Hieromonk Dr Hilarion Alfeyev, Russian Orthodox Church, Russian Federation
• H.E. Metropolitan Ambrosios of Kalavryta, Church of Greece, Greece
• Mr George Andriadze, Georgian Orthodox Church, Georgia
• Mr Andrei Dan Apostu, Orthodox Church in Czech Lands and Slovakia, Czech Republic
• H.E. Metropolitan Athanasios Papas, Ecumenical Patriarchate of Constantinople, Turkey (Substitute for: H.E. Metropolitan Ambrosius of Oulu)
• Mr Ramez Attalah, Synod of the Nile of the Evangelical Church, Egypt
• H.E. Archbishop Aghan Baliozian, Armenian Apostolic Church (Etchmiadzin), Australia
• H.E. Metroplitan Anba Bishoy of Damiette, Coptic Orthodox Church, Egypt
• Bishop Gustáv Bölcskei, Reformed Church in Hungary, Hungary
• Ms Manoushag Boyadjian, Armenian Apostolic Church (Cilicia), Lebanon
• Mr John Briggs, Baptist Union of Great Britain, United Kingdom
• H.E. Metropolitan Chrysostomos of Ephesus, Ecumenical Patriarchate of Constantinople, Greece
• H.E. Metropolitan Chrysostomos Zafiris, Church of Greece, Greece
  (Substitute for H.E. Metropolitan Ambrosius of Kozani)
• H.G. Bishop Chrystopher of Olomouc and Brno, Orthodox Church in Czech Lands and Slovakia, Czech Republic
• Rev. Yadessa Daba, Ethiopian Evangelical Church Mekane Yesus, Ethiopia
• Mr Jean Fischer, National Protestant Church of Geneva, Switzerland
• Rev. Ying Gao, China Christian Council, China
• Rev. Fr Dr K.M. George, Malankara Orthodox Syrian Church, India
• Bishop Hans Gerny, Old Catholic Church of Switzerland, Switzerland
• Ms Anne Glynn-Mackoul, Greek Orth. Patr. of Antioch and All the East, United States of America
• Ms Eden Grace, Society of Friends, United States of America
• Rev. Wesley Granberg-Michaelson, Reformed Church in America, United States of America
• H.E. Mar Gregorios Yohanna Ibrahim, Syrian Orthodox Church of Antioch, Syria
• Fr Mikhael Gundyaev, Russian Orthodox Church, Switzerland
• Mr Gabriel Habib, Greek Orthodox Patriarchate of Antioch and All the East, United States of America
• Bishop Dr Thomas L. Hoyt Jr, Christian Methodist Episcopal Church, United States of America
• Bishop Voitto Huotari, Evangelical Lutheran Church of Finland, Finland
• H.E. Archbishop Jeremiasz of Wroclaw, Polish Autocephalic Orthodox Church, Poland
• Ms Jana Kalinová, Czechoslovak Hussite Church, Czech Republic
• H.G. Bishop Basil Karayiannis of Trimithus, Church of Cyprus, Cyprus
• The Very Rev. Leonid Kishkovsky, Orthodox Church in America, United States of America
• Bishop Dr Rolf Koppe, Evangelical Church of Germany, Germany
• Dr John Lappas, Orthodox Autocephalous Church of Albania, Greece
• Dr Janice Love, United Methodist Church, United States of America
• Archbishop Makarios Tillyrides of Zimbabwe, Greek Orthodox Patriarchate of Alexandria, Zimbabwe
• H.G. Abune Mekarios, Ethiopian Orthodox Tewahedo Church, Ethiopia
• D. Dr Soritua Nababan, Huria Kristen Batak Protestan, Indonesia
• H.G. Bishop Dr Nifon of Slobodzia & Calarasi, Romanian Orthodox Church, Romania
• Dr Mercy A. Oduyoye, Methodist Church of Nigeria, Ghana
• Archbishop Michael Peers, Anglican Church of Canada, Canada
• H.E. Metropolitan John Pelushi, Orthodox Autocephalous Church of Albania, Albania
• Rev. John Phiri, Reformed Church in Zambia, Zambia
• Dr Agidew Redie, Ethiopian Orthodox Tewahedo Church, Ethiopia
• Fr Dr Ioan Sauca, Romanian Orthodox Church, Switzerland
  (Substitute for Rev. Prof. Dr Ioan Ica, Jr.)
• Prof. Constantine Scouteris, Greek Orthodox Patriarchate of Alexandria and All Africa, Greece
• Archpriest David Sharashenidze, Georgian Orthodox Church, Georgia
• Dr Mary Tanner, Church of England, United Kingdom
• Bishop Dr Zacharias M. Theophilus, Mar Thoma Syrian Church of Malabar, United States of America
• Very Rev. Dr Georges Tsetsis, Ecumenical Patriarchate of Constantinople, Switzerland
• Rev. Dr Eugene Turner, Presbyterian Church (USA), United States of America
• Rev. Dr d'Arcy Wood, Uniting Church in Australia, Australia

Personnes excusées/absentes :

• Dr Agnes Abuom, Anglican Church of Kenya
• Bidhop Vinton R. Anderson, African Methodist Episcopal Church (USA)
• H.E. Metropolitan Aristarchos of Constantine, Greek Orthodox Patriarchate of Jerusalem Bulgarian Orthodox Church
• H.E. Bishop Ignatije of Branicevo, Serbian Orthodox Church
• H.E. Bishop Irenej of Backa, Serbian Orthodox Church
• Bishop Dr Christoph Klein, Evangelical Church of the Augsburg Confession in Romania
• Archbishop N.W.H. Ndungane, Church of the Province of Southern Africa
• Rev. Ofelia Ortega, Presbyterian Reformed Church in Cuba
• Bishop Federico J. Pagura, Evangelical Methodist Church of Argentina
• Rev. Dr Jong-Wha Park, Presbyterian Church in the Republic of Korea
• Dr George Sabra, Reformed Church/Lebanon
• Bishop Munib Younan, Evangelical Lutheran Church/Jerusalem

Invités :

• Mr Andrei Elisseev, Russian Orthodox Church
• H.E. Metropolitan Gennadios Limouris of Sassima, Ecumenical Patriarchate of Constantinople
• Archimandrite Benedict Ioannou, Ecumenical Patriarchate of Constantinople