95 All this however must always be done in communion. When the Catholic Church affirms that the office of the Bishop of Rome corresponds to the will of Christ, she does not separate this office from the mission entrusted to the whole body of Bishops, who are also "vicars and ambassadors of Christ". The Bishop of Rome is a member of the "College", and the Bishops are his brothers in the ministry. Whatever relates to the unity of all Christian communities clearly forms part of the concerns of the primacy. As Bishop of Rome I am fully aware, as I have reaffirmed in the present Encyclical Letter, that Christ ardently desires the full and visible communion of all those Communities in which, by virtue of God's faithfulness, his Spirit dwells. I am convinced that I have a particular responsibility in this regard, above all in acknowledging the ecumenical aspirations of the majority of the Christian Communities and in heeding the request made of me to find a way of exercising the primacy which, while in no way renouncing what is essential to its mission, is nonetheless open to a new situation. For a whole millennium Christians were united in "a brotherly fraternal communion of faith and sacramental life ... If disagreements in belief and discipline arose among them, the Roman See acted by common consent as moderator". In this way the primacy exercised its office of unity. When addressing the Ecumenical Patriarch His Holiness Dimitrios I, I acknowledged my awareness that "for a great variety of reasons, and against the will of all concerned, what should have been a service sometimes manifested itself in a very different light. But ... it is out of a desire to obey the will of Christ truly that I recognize that as Bishop of Rome I am called to exercise that ministry ... I insistently pray the Holy Spirit to shine his light upon us, enlightening all the Pastors and theologians of our Churches, that we may seek—together, of course—the forms in which this ministry may accomplish a service of love recognized by all concerned".
Source: Ut Unum Sint (Vatican.va)