The Bishop of Antwerp supports the Catholic Church embracing same-sex partnerships and wants it bless their relationships with an alternative to marriage.
Johan Bonny is known as an outspoken priest and is expected to air his views at the October Synod on the Family, according to Gay Star News.
He has openly called for Pope Francis to revisit the church's views on relationships and human sexuality.
The bishop has been campaigning for Catholicism to find new ways of recognising same-sex couples within the church, whilst at the same time maintaining the sanctity of heterosexual marriage.
Last year he circulated a 22 page open letter to Synod delegates urging them to modernize the church's teachings on same-sex relationships.
He told the Belgian newspaper De Morgen: "Inside the Church, we must look for a formal recognition of the relational dimension that is also present in many homosexual, lesbian and bisexual couples.
"In the same way that in society there exists a diversity of legal frameworks for partners, there must be a diversity of forms of recognition in the Church."
In 2014 Belgium's delegate to Synod was conservative Archbishop Joseph Leonard, who retired in May, and the Bishop of Antwerp was chosen to be 2015 delegate.