Fr. Vasily participated in various international scientific congresses and conferences, making presentations at them. Among these conferences, the First International Congress of Patrologists in Oxford (1951) and the Congress of Byzantinologists in Munich (1958) should be especially noted. Subsequently, congresses of patrologists were convened in Oxford every four years, and Father Vasily spoke at them with reports. In November 1959, he participated in the celebrations on the occasion of the 600th anniversary of the repose of St. Gregory Palamas, Archbishop of Thessalonica.

On May 26, 1958, by a decree of His Holiness Patriarch Alexy and the Holy Synod, Archimandrite Basil was appointed vicar of the Patriarchal Exarch for Western Europe, Archbishop Nicholas (Eremin, +1985) with the title of "Bishop of Volokolamsk" and a stay in Paris. The consecration of Archimandrite Basil was performed on June 14, 1959 in London, in the Dormition Cathedral of the Russian Orthodox Church, by Archbishop Nicholas, Patriarchal Exarch for Western Europe, and Bishop Anthony (Bloom; now Metropolitan of Sourozh). The Greek bishop in London, Jacob Virvos (Patriarchate of Constantinople), also took part in the nomination of bishop.

On May 30, 1960, after the death of Metropolitan Alexander (Nemilovsky; +1960) of Brussels and Belgium, Bishop Basil was appointed by decree of His Holiness Patriarch Alexy and the Holy Synod to the Brussels cathedra. In the same year, Bishop Basil visited Moscow, where on July 21, the feast day of the Kazan Icon of the Mother of God, he was elevated to the rank of archbishop. The Brussels diocese is small in terms of the number of believers and churches. During his administration, Archbishop Basil opened three new churches: two in Brussels and one at the Flemish skete in Perveys, near Dixmude. Services in Brussels churches are performed in French, and in Pervaise in Flemish. In 1985, Vladyka Basil had the pleasure of seeing the official recognition by the Belgian authorities of the Orthodox faith, along with the Roman Catholic (with the representatives of the hierarchy of which he maintained friendly relations) and others.

Devoting much energy to his archpastoral duties, Vladyka Basil did not abandon his scholarly work, the main fruit of which was the critical commented edition of the "Catechetical Homilies" of St. Symeon the New Theologian, which he began in Oxford, in the patristic series Sources Chretiennes. For this valuable work for theological science (on which he worked for almost fifteen years, studying numerous manuscripts), the Council of the Leningrad Theological Academy awarded him the degree of Doctor of Theology. As a result of these many years of labor, Archbishop Basil also wrote a large study "St. Symeon the New Theologian. Life, Spirituality, Teaching", published in Russian in Paris in 1980. A French translation, Dans la lumiere du Christ (In the light of Christ), was published in the same year by the Shevton Monastery. The Greek translation of Mesa sto fos tou Christou (In the light of Christ) was published in Thessaloniki in 1983. An English translation is currently being prepared for publication in the United States.

Archbishop Basil participated in the delegations of the Moscow Patriarchate in three Pan-Orthodox Conferences on the island of Rhodes (1961-1964) and in the 4th Conference (1968) in Chambesy (Switzerland). By the decision of the Holy Synod of August 5, 1965, Archbishop Basil was appointed a member of the Inter-Orthodox Commission for Dialogue with the Anglican Church from the Russian Orthodox Church. The Anglican side highly appreciated the contribution to the development of dialogue by Vladyka Basil, who had the gift of combining moderation in his speeches with the uncompromising Orthodox views.

Being deeply devoted to the Russian Church, Vladyka Vasily grieved over her state of servitude in relation to the Soviet state. His voice was one of the few voiced during the sessions of the Moscow Council in May 1971, when he spoke in favor of a secret ballot in the election of the future Moscow Patriarch. One of the important acts of the Council, in addition to the election of the Patriarch, Archbishop Basil considered the Act on the abolition of the oaths of the Moscow Council of 1656 and the Great Moscow Council of 1667, imposed on the old rites and on those who adhere to them. After that, he was present at the enthronement of His Holiness Patriarch Pimen in the Epiphany Patriarchal Cathedral.

On September 7, 1985, Vladyka Basil returned to his homeland. It pleased God's Providence that he take part in the celebrations on the occasion of the namesday of His Holiness Patriarch Pimen for the last time in the Epiphany Patriarchal Cathedral on September 9. On September 15, the 150th Sunday after Pentecost, Archbishop Vasily, together with Metropolitan Anthony of Leningrad and Novgorod, celebrated his last Divine Liturgy at the Transfiguration Cathedral in Leningrad, the same church where the Sacrament of Holy Baptism was performed over him 85 years ago. After the liturgy, he felt bad. Doctors diagnosed a stroke. Shortly before his death, the canon for the departure of the soul was read. At dawn on September 22, 1985, he peacefully reposed in the Lord.