7 "The Lord of the Ages wisely and patiently follows out the plan of his grace on behalf of us sinners. In recent times he has begun to bestow more generously upon divided Christians remorse over their divisions and a longing for unity. Everywhere, large numbers have felt the impulse of this grace, and among our separated brethren also there increases from day to day a movement , fostered by the grace of the Holy Spirit, for the restoration of unity among all Christians . Taking part in this movement, which is called ecumenical, are those who invoke the Triune God and confess Jesus as Lord and Saviour. They join in not merely as individuals but also as members of the corporate groups in which they have heard the Gospel, and which each regards as his Church and, indeed, God's. And yet almost everyone, though in different ways, longs that there may be one visible Church of God , a Church truly universal and sent forth to the whole world that the world may be converted to the Gospel and so be saved, to the glory of God".
Source: Ut Unum Sint (Vatican.va)