Is it permissible to donate the organs of a non-Muslim who is not under a treaty after his death?

The questioner : This is a question about our previous topic. I wanted to refer to it, but the Shaykh, may Allah reward him with good, pointed out something important. That is whether it is permissible or not permissible to donate the organs of a non-Muslim who is not under a treaty.

The Shaykh : After...

The questioner : After his death?

The Shaykh : I said that doctors today say that we dissect some corpses for the purpose of practice or discovering certain diseases. We answered that this is not permissible due to the hadith we mentioned earlier. However, I noticed in the established narration that contains the word "believer" that this has an implication . So I said: If it is absolutely necessary that practice for discovering certain ailments or diseases cannot be done except through the corpse of a deceased person, then let it be the corpse of a non-Muslim, by way of taking the lesser of two harms.
The questioner : Yes, I do.