"I further pledge to conduct a thorough investigation in search of the truth into the troubling allegations against Bishop Bransfield and to work closely with clergy, religious leaders of the diocese until the appointment of a new bishop".
The development, announc- ed just as a highly anticipated meeting between Francis and United States cardinals and bishops was beginning, lent a dramatic twist to the emergency gathering, called to address another scandal involving an ex-US cardinal.
Interested in Pope Francis? Since the release, an archbishop claimed Pope Francis had helped hide an American cardinal's alleged abuse.
Vigano, a former Vatican envoy to Washington, also called on the pope to step down.
The head of the Pontifical Commission for the Protection of Minors, Cardinal Sean O'Malley, and two USCCB officials will also attend today's meeting.
Francis's key cardinal advisers announced the decision Wednesday, a day before Francis meets with US church leaders who have been deeply discredited by the latest accusations in the Catholic Church's decades-long sex abuse and coverup scandal.
The Vatican said that a West Virginian bishop, Michael Bransfield, who resigned yesterday, was being investigated for molesting adults.
The damning report echoes the recent findings of a Pennsylvania grand jury, which examined clerical sex abuse in six dioceses over 70 years, detailing credible allegations of abuse from some 300 priests, deacons, and seminarians.
In February, Catholic bishops from across the world will convene in Rome at the pope's invitation to discuss the "prevention of abuse of minors and vulnerable adults".
The head of the USA bishops' conference, Cardinal Daniel DiNardo, the archbishop of the Galveston-Houston area in the southwestern state of Texas, and other Catholic leaders in the United States say they want answers from the pontiff about allegations he knew years ago about credible information that Archbishop Theodore McCarrick of Washington had abused a teenage altar boy in the 1970s and other seminarians and young priests, but did not confront McCarrick about the allegations. He had said he wanted to discuss further action to deal with and stop cases of clerical sexual abuse in the USA, including how to make bishops more accountable for their actions or punishable for their mismanagement.
He added: "Elitism, clericalism fosters every form of abuse".
On Wednesday, German media reported that a church-commissioned study on abuse in the German church detailed 3,677 abuses cases between 1946 and 2014, with more than half of the victims aged 13 or younger and most boys.