The Vatican has announced the unexpected conclusion of a controversial overhaul of the main umbrella group of U.S. nuns — a major shift in tone and treatment of American nuns under the social justice-minded Pope Francis.

The Vatican said Thursday it had accepted a final report on its overhaul of the Leadership Conference of Women Religious and declared that the "implementation of the mandate has been accomplished."

When the Vatican's Congregation for the Doctrine of the Faith took over the LCWR in 2012, it accused the group of taking positions that undermined Catholic teaching on the priesthood and homosexuality while promoting "certain radical feminist themes incompatible with the Catholic faith."

It envisioned a five-year overhaul, fueled by concerns among U.S. conservatives that the group had strayed from church teaching.