[2] In 1947 Sipovich moved to Great Britain to serve the spiritual needs of thousands of ethnic Belarusians (mainly former soldiers of the Polish Anders Army) who settled there after World War II.

He joined the recently founded Association of Belarusians in Great Britain and was involved in refugee welfare work.

At that time, he also revived the Society of St John Chrysostom, an organisation devoted to promoting a better knowledge and understanding of Eastern Christianity among English-speaking people.

Bishop Sipovich also served as Superior General of the Congregation of Marian Fathers from 1963 to 1969 and was Apostolic Visitor for Belarusian Catholic faithful abroad.

Bishop Sipovich died at the age of 67 on 4 October 1981 and is buried in St Pancras and Islington Cemetery in East Finchley, North London.