Yahya bin Wathhab (may Allah have mercy on him) narrates from Masruq (may Allah have mercy on him): When a man says to his wife: "Your affair is yours" and "Choose," or gives her away to her family, it is one separating (irrevocable) divorce.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الخلع والطلاق / 15034