What is the ruling on anal intercourse with one's wife, even if it occurred by mistake?

It is impermissible for a man to intentionally engage in anal intercourse with his wife, due to Allah Almighty's saying: ﴿So approach them from where Allah has commanded you﴾, and due to the Prophet's (peace be upon him) saying: "Accursed is he who has intercourse with his wife in her anus." Scholars have agreed upon the prohibition of this. However, if one engages in anal intercourse with his wife by mistake and without intention, then there is no sin upon him, due to the Prophet's (peace be upon him) saying: "Indeed, Allah has forgiven my nation for mistakes, forgetfulness, and what they are forced to do."