VATICAN CITY — The Order of Malta, the ancient Roman Catholic aristocratic lay order, has told Pope Francis that his decision to launch an investigation into the ouster of a top official over a condom scandal is “unacceptable.”

In an extraordinary rebuke of the pontiff, the group said the replacement of its grand chancellor was an “act of internal governmental administration of the Sovereign Order of Malta and consequently falls solely within its competence.”

Francis on Thursday appointed a five-member commission to investigate the ouster of Albrecht von Boeselager amid evidence that Francis’ own envoy to the group helped engineer it without his blessing.

One charge used against von Boeteslager concerned a program that the order’s aid group participated in several years ago to help sex slaves in Myanmar, including giving them condoms to protect against HIV infection. Church teaching bars artificial contraception.

An internal investigation was conducted and von Boeselager admitted he knew about the condoms, which were distributed by other aid programs, not his. The Vatican was informed, Malteser International’s participation in the program ended and an ethics committee was launched to ensure that future projects adhered to Catholic Church teaching, the officials said.

In a statement, von Boeselager said he had been asked to resign during a Dec. 6 meeting attended by Burke. During the meeting, the order’s grand master indicated that the request to resign “was in accordance with the wishes of the Holy See.”

However, no such request was ever made. Von Boeselager said since his ouster, the Holy See has written to the order “confirming that such a wish was never raised.”

By naming an independent commission to look into the case, Francis appears to be seeking an objective assessment of von Boeselager and his ouster without the input of Burke, who has been among Francis’ fiercest critics.

Burke is one of four cardinals who have publicly questioned Francis’ flexible approach to whether civilly remarried Catholics can receive Communion. Burke, a native of Richland Center, Wis., is a hard-liner on the issue, as well as on the absolute prohibition on the use of artificial contraception.

Francis removed him as the Vatican’s supreme court justice in 2014 and named him to be the patron of the Order of Malta, an ancient Catholic order that runs hospitals and clinics around the world and has an army of volunteers who respond to natural disasters and war zones.