Mikhwal bin Rashid narrates from Abu Ja'far (may Allah have mercy on him) concerning (saying) "forbidden", that is, when the husband says to his wife, "You are forbidden to me": if the husband intended divorce, it will be one divorce and the husband has the right to take her back; and if the husband did not intend divorce, it is an oath for which he will give expiation.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الخلع والطلاق / 15064