France has received a request from Canada to extradite retired Roman Catholic priest Johannes Rivoire so he can face a charge of sexual abuse from when he worked in Canada's North, a French diplomatic source said.

Canada's northern indigenous people, the Inuit, plan to press the Pope Francis while he is on a visit on Friday to help return Rivoire to Canada.

"An extradition request concerning Mr. Johannes Rivoire has been transmitted to France by Canada's judicial authorities," the diplomatic source told Reuters. "This request is currently being processed by the Ministry of Justice, which has asked Canadian authorities for additional information."

It was not clear what information France is seeking or when Canada made the request.

Canada's justice department could not be immediately reached for comment. It has previously declined to comment on whether it asked France to extradite Rivoire, saying such requests are confidential.

The extradition treaty between Canada and France states that neither country is bound to extradite its own nationals.

Rivoire, 93, is charged with sexual assault related to his work in northern parishes for the Catholic congregation Missionary Oblates of Mary Immaculate. The charge against Rivoire, who lives in Lyon, France, was laid by Canadian police in February.

A woman alleged that Rivoire sexually assaulted her between 1974 and 1979 when she was a young girl. Neither the charge nor any allegations against Rivoire have been proven in court.

Inuit have long alleged that Rivoire sexually abused children during his work in northern Canada from the 1960s to 1993. Rivoire has not responded to a Reuters request for comment.

During his visit to Canada, Pope Francis intends to apologise for abuses of indigenous children in government schools largely run by the Catholic church.