Pope Francis is now concluding a six-day long visit to Canada, where the purpose was to contribute to reconciliation and healing for the abuses that the Catholic Church subjected more than 150,000 children to between the years 1831 and 1996.

On the way home, the 85-year-old pope says he must slow down or step aside altogether.

The reason is the pope's knee problems, which have gotten worse recently. 

"A Pope can be replaced"

The Pope believes that the trip to Canada was "a test" to see if he can continue at the same pace, which he now states that he cannot.

The trip to Canada was the first in which the pope used a wheelchair and cane to get around, which he said limited his schedule and activities. 

- I think that at my age and with my knee problems, I have to take it easy in order to serve the church.

Alternatively, maybe think about whether I should possibly step aside, he tells the journalists aboard his private plane.

The Pope has previously never considered retiring but says he may not have a choice and is keeping the door open: 

- It is not strange.

It's not a disaster.

It is possible to replace a pope.

On the plane home, he also states that he is open to discussing the Catholic Church's "absolute no" to contraception and that he would like to visit the Ukrainian capital, Kyiv.

The abuses a "genocide"

During the trip to Canada, the Pope apologized for what he now calls "genocide" against the indigenous population.

- I didn't say the word because I didn't think of it at the time, but I described genocide, didn't I?, says the Pope on the grounds that he only called the abuses genocide on Saturday and continued:

- I apologized, I asked for forgiveness for this work, which involved genocide.

Between the years 1831 and 1996, an estimated 150,000 children from the indigenous population were exposed to various kinds of abuse in specially established boarding schools.

The system was based on the children being forcibly separated from their families to be indoctrinated in Western values ​​through religious schools.

Both physical and sexual abuse occurred combined with denial of the children's own cultures and languages.

Last year, the remains of 215 children were found at one of the boarding schools.