The Messenger of Allah ﷺ carried out the procedure of mutual cursing between Uwaymir and his wife. Uwaymir then said, "Messenger of Allah, if I keep her, I will have lied against her."So he separated from her before the Messenger of Allah ﷺ commanded him to do so, and this became the established practice for the Mutalaineen.
أن رسول الله ﷺ لا عن بين عويمر وبين امرأته. فقال عويمر: إن انطلقت بها يا رسول الله لقد كذبت عليها. قال: ففارقها قبل أن يأمره رسول الله ﷺ فصارت سنة المتلاعنين.
Imam Ahmad (22830) narrated it from Abu Kamil, who said, Ibrahim bin Saad narrated to us, who said, Ibn Shihab narrated to us, from Sahl bin Saad, and he mentioned it within a long hadith. Its basic account is found in the Sahihayn and other collections. On this subject there is also what has been narrated from Ibn Masud and Ali as well, but the sahih version is what I have mentioned.