Umar bin Khaldah Al-Ansari narrated from his mother (may Allah be pleased with her) that the Messenger of Allah (peace and blessings be upon him) sent Sayyiduna Ali (may Allah be pleased with him) during the days of Tashreeq, so he announced that these are days of eating, drinking, and intimacy (with one's wife), not for fasting.
Hadith Referenceمسند اسحاق بن راهويه / كتاب الصوم / 423
Hadith Takhrij«سنن دارقطني ، كتاب الصيام ، باب طلوع الشمس بعد الفطار : 212/2 .»