Ali bin Abi Talhah (may Allah have mercy on him) narrates from Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) concerning the verse: "Allah has ordained for you the expiation of your oaths" [Surah al-Tahrim: 2], that Allah Almighty commanded His Prophet (peace and blessings be upon him) and the believers that when they make something Allah has made lawful forbidden for themselves, its expiation is that of an oath: feeding ten poor people, or clothing them, or freeing a slave. Divorce does not enter into this.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الخلع والطلاق / 15058