The Parish Priests Initiative, an Austria-based group of Catholics led by Father Helmut Schueller, issued a statement saying its members are "deeply appalled" by the Roman Catholic Church's March 15 release, which was notably approved by Pope Francis before its publication.
"We members of the Parish Priests Initiative are deeply appalled by the new Roman decree that seeks to prohibit the blessing of same-sex loving couples. This is a relapse into times that we had hoped to have overcome with Pope Francis," the group statement read, as reported by Reuters.
"We will -- in solidarity with so many -- not reject any loving couple in the future who ask to celebrate God’s blessing, which they experience every day, also in a worship service."
The Parish Priests Initiative is composed of more than 350 members from the official Church and has around 3,000 lay supporters, according to Reuters.
Schuller, who was a former deputy to Vienna archbishop Cardinal Christoph Schoenborn, was stripped of his title by the Church in 2012.
While the initiative has gained support from priests in both the US and Europe, it has also been critiqued for calling on the Vatican to do away with priestly celibacy. Many members of the group also advocate for the ordination of women.
Additional groups and individuals belonging to the 1.3 billion-member Roman Catholic Church have expressed that if the Vatican fails to modernize its approach to same-sex unions, then lay Catholics will have to step in.
"If priests and pastoral ministers no longer feel they can perform such a blessing, the Catholic laity will step in and perform their own rituals," Francis DeBernardo, executive director of New Ways Ministry - a church that advocates for lesbian, gay, bisexual, and transgender Catholics, told the Associated Press on Monday.
Robert Shine, associate director of the ministry, published an op-ed on Tuesday in which he slammed the Vatican's statement as a product of "misguided logic."
"It seems church leaders have yet to learn a simple lesson: you cannot just order the faithful to stop conversing about a disputed topic," Shine wrote. "This approach did not work with birth control in the 1960s, nor with the discussion over women priests in the 1990s, and it will not work now."