On [[April 16|16 April]] 1988 he was unanimously elected by the Sacred Synod of the Ecumenical Patriarchate as ''Archbishop of Thyateira and Great Britain'' and his enthronement took place at the Cathedral of Sophia in West London. His tireless program sees him attending many community events, both in London and around the country. His quiet and reasoned voice upholds both the concerns of the Greek Orthodox community and expresses the Christian message of peace and reconciliation. During the Kosovo conflict, in 1999, between the local Albanians and the Serbian army where NATO forces intervened, he was interviewed on BBC radio. Through his questions, the journalist appeared keen for Gregorios to side with the (fellow) Orthodox Serbs and criticize NATO. His Eminence simply stated that it was time for reconciliation and especially a time "of repentance for all of us."
link==*[http://www.thyateira.org.uk Archdiocese of Thyateira and Great Britain]*[http://orthodoxresearchinstitute.org/resources/hierarchs/constantinople/great_britain/current.htm#gregorios_arch_thyateira Listing at the Orthodox Research Institute ]